Taxonomy of Dissomphalus Ashmead (Hymenoptera, Bethylidae) from Fiji and Solomon Islands, with Description of Twenty-Seven New Species ^†

Abstract

This study presents a comprehensive taxonomic revision of the genus Dissomphalus Ashmead (Hymenoptera, Bethylidae) in the southwestern Pacific, focusing on specimens from Fiji and the Solomon Islands. Dissomphalus is the most species-rich genus within Bethylidae, with a global distribution, yet it remains poorly documented in the Oceanian region. We examined 151 male specimens collected in these islands. As a result, we describe 27 new species, 25 from Fiji and 2 from the Solomon Islands. Diagnostic morphological features, detailed illustrations, and an identification key for all species are provided. These findings substantially expand the known diversity of Dissomphalus in Oceania. Our results underscore the importance of taxonomic research in underexplored regions and highlight the potential for high levels of species endemism in island ecosystems. This revision contributes to a better understanding of the genus’ biogeographical distribution and provides essential tools for future biodiversity assessments and conservation efforts in the southwestern Pacific.

1. Introduction

Dissomphalus Ashmead, 1893, is the most species-rich genus within the family Bethylidae, currently comprising 597 valid species with a cosmopolitan distribution [1,2,3]. The genus is morphologically distinguished by the presence of a tergal process on the second metasomal segment and by the divided aedeagus in the male genitalia, consisting of dorsal and ventral valvae [1]. These features have proven essential for species delimitation and the organization of species into morphological groups [4], which has facilitated regional and group-level taxonomic revisions.

Recent efforts have considerably expanded our knowledge of Dissomphalus diversity in specific regions, especially the Neotropical [2,5,6,7] and Afrotropical regions [3]. Notably, the revision of the punctatus species-group [2] and the Afrotropical fauna [3] together revealed over 150 new species, highlighting the hidden diversity of the genus.

Nevertheless, significant knowledge gaps remain in other parts of the world, particularly in the Australian and Oceanian regions, where the genus has received limited attention despite its potential for high endemism and richness.

Taxonomic research on Dissomphalus in the Oceanian region has historically been scarce and sporadic. The only significant contribution to date was a comprehensive study that described 91 new species from Indonesian New Guinea and Papua New Guinea, including the Bismarck Archipelago, based on just 388 male specimens [8]. This represents an impressive ratio of approximately one species for every 4.3 specimens examined, underscoring both the taxonomic complexity of the genus and the exceptional species richness concentrated within relatively small sample sizes. In comparison, a revision of the Afrotropical fauna recognized 127 species based on 1585 male specimens, yielding a ratio of 1 species per 12.5 specimens, further illustrating the remarkable diversity of Dissomphalus even in regions with broader sampling [3].

In this context, the present study seeks to advance the alpha-taxonomic knowledge of Dissomphalus in the Oceanian region, with particular emphasis on Fiji and the Solomon Islands. Here, we describe 27 new species from Fiji and two from the Solomon Islands, provide a taxonomic key, and offer new insights into the morphological diversity and regional distribution of Dissomphalus in the southwestern Pacific.

2. Materials and Methods

A total of 151 specimens of Dissomphalus were examined, collected from Fiji and the Solomon Islands. These specimens are deposited in the Bernice Pauahi Bishop Museum (BPBM, Hawaí), Núcleo de Excelência em Sistemática de Bethylidae (NESB, Brazil) and the Queensland Museum South Bank (QMSB, Australia).

To ensure accurate species delimitation and avoid redundancy with previously described taxa, we compared all examined material with published descriptions and figures, particularly those from the comprehensive revision of Dissomphalus species from Indonesian New Guinea and Papua New Guinea [8]. These comparisons are presented in the subsection “Comparison with Oceanian congeners” within each species description, which provides comparative remarks between the species described herein and previously published Dissomphalus species from the Oceanian region.

We adopted the classification of the biogeographical regions proposed by Holt et al. [9]. Accordingly, the Oceanian region is understood to comprise New Guinea, the Bismarck Archipelago, the Solomon Islands, Fiji, and other Pacific islands located east of Wallace’s Line and north of New Zealand.

Species descriptions were elaborated using Descriptive Language for Taxonomy DELTA) [10] and conducted under a stereoscopic microscope with incident light. Morphological terminology [11] and integumental sculpture nomenclature are presented in the following section [12].

Measurements of the main structures were taken using a stereomicroscope equipped with a 16× eyepiece and a micrometric reticle with 10 divisions per centimeter.

For detailed examination and subsequent illustration, male genitalia were cleared using the Proteinase K protocol [13]. Illustrations of the male genitalia for each species were produced using a Leica DM2500 microscope equipped with a camera lucida. The drawings were scanned in Photoshop and saved at 600 dpi resolution. Additional morphological characteristics, such as the head, and tergal processes, were photographed using a Leica Z16 APO stereomicroscope fitted with a magnifying lens and a Leica Flexacam C3 video camera (Leica Microsystems, Wetzlar, Germany), under illumination provided by a Modular Dome LED Illumination System [14]. The photographs were automatically combined into a single image using Helicon Focus, Version 8.3.0. (HeliconSoft Ltd., Kharkiv, Ukraine), employing Method C (Pyramid), and saved at 300 dpi resolution.

We adhere to the operational species concept proposed by [15], which defines a species as the smallest group that is consistently and morphologically distinct from similar groups. To assist in the identification of the species recognized in this study, we used the identification keys developed by [8,16] for the faunas of Thailand and Papua New Guinea, respectively.

Data presented in the “Material examined” section are transcribed exactly as they appear on the specimen labels. All specific epithets of the new species described herein are dedicated to Fijian deities, in honor of the gods of Fijian mythology, recognizing their cultural and spiritual significance and highlighting the connection between the region’s biodiversity and its cultural heritage.

3. Results

We recognize a total of 27 new species of Dissomphalus in Fiji and the Solomon Islands.

3.1. New Species Description

Dissomphalus abaiae Nunes, Azevedo & Colombo sp. nov.

Figure 1A, Figure 4A and Figure 6A,B

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 3–20.XII.2002, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 166363 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I., 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary, 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166008 (NESB); 3 males, same data as holotype except: 2–10.X.2002, FBA 164688, 164690, 164694 (NESB); 1 male, 14–21.XI.2002, FBA 164267 (NESB); 1 male, 21.XI-13.XII.02, FBA 164760 (NESB); 4 males, FBA 166357, 166359, 166361, 166369 (NESB); 3 males, 27.XII.2002–3.I.2003, FBA 146442, 146443, 146445 (NESB); 1 male, 30.VI-31.VII.04, FBA 148608 (NESB); 1 male, 5.6 km SE Tavuki Vlg., Mt. Devo Peak, 1187 m, 30.VI-14.VIII.2004, Malaise 1, coll. Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 150870 (NESB); 2 males, 892 m, 14–31.VII.2004, Malaise 4, coll. E.I. Schlinger, M. Tokota’a., 16.837° S, 179.973° W, FBA 151757, 151761 (NESB); Viti Levu, 10 males, 1.1 km SSW, Volivoli Vlg., Sigatoka Sand Dunes, 55 m, 8.X.-14.XII.2002, Malaise 2, coll. Schlinger, M. Tokota’a., 18.169 S, 177.485 E., FBA 093211, 093212, 093216, 093217, 093218, 093219, 093220, 093222, 093223, 093224 (NESB).

Description. Male. Body length: 2.32 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head almost as long as wide (Figure 1A); mandible with two apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 4A), with depression shallow, circular and small, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6A), shorter than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 6B), slightly bifid, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin abruptly acute, ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet abaiae refers to Abaia, the Fijian goddess of the freshwater lakes and rivers.

Differential diagnosis. This species is similar to D. burotuensis sp. nov., displaying mandibles with two apical teeth, a head almost as long as wide, and the metasomal segment II with the lateral tergal process. However, D. abaiae sp. nov. has the median clypeal lobe with three apical teeth, the tergal process with a large tubercle, and long aedeagal outer lobes, whereas D. burotuensis sp. nov. has a median clypeal lobe with two apical teeth, the tergal process with a small tubercle, and very short aedeagal outer lobes.

Comparison with Oceanian congeners. This species is similar to D. wetliva Mugrabi & Azevedo, 2016 from Indonesia by displaying the median clypeal lobe tridentate and the metasomal segment II with the lateral tergal process bearing a small and shallow depression. However, D. abaiae sp. nov. has the apex of harpe strongly curved laterad, and the aedeagal dorsal valves progressively narrowing apicad, whereas D. wetliva has the apex of harpe slightly curved laterad, and the aedeagal dorsal valves entirely wide.

Distribution. Fiji (Kadavu, Taveuni, and Viti Levu Islands).

 

Dissomphalus bului Nunes, Azevedo & Colombo sp. nov.

Figure 1B and Figure 6C,D

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 31.X–14.XI.02, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 149397 (NESB)”.

Description. Male. Body length: 2.90 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 1B); mandible with two apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with apical three teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures very small; vertex crest weakly outcurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II without tergal process. Genitalia: Harpe with dorsal margin wide basally (Figure 6C), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex posterior to dorsal valve (Figure 6D), simple, wide, abruptly narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet bului refers to Bulu, the Fijian god of the underworld.

Differential diagnosis. This species is similar to D. naqaii sp. nov. by having the mandibles with two apical teeth and the metasomal segment II without the tergal process. However, D. bului sp. nov. has the trapezoidal median clypeal lobe and the long outer aedeagal lobes, whereas D. naqaii sp. nov. has the tridentate median clypeal lobe and the short outer aedeagal lobes.

Comparison with Oceanian congeners. This species is similar to D. nek Mugrabi & Azevedo, 2016 from Papua New Guinea by having the median clypeal tooth rounded, and the metasomal segment II without tergal process. However, D. bului sp. nov. has the mandibles with two apical teeth, and the aedeagal ventral valves abruptly narrowing apicad, whereas D. nek has the mandibles with three apical teeth, and the aedeagal ventral valves progressively narrowing apicad.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus burotuensis Nunes, Azevedo & Colombo sp. nov.

Figure 1C, Figure 4B and Figure 6E,F

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Type material. Holotype: male labeled: “FIJI, Kadavu I., 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary, 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a. 19.078° S, 178.121° E. FBA166005”. Paratypes: FIJI, 1 male, Taveuni, Cakaudrove Prov., 5.5 km SE Tavuki Vlg., Mt. Devo Peak, 1188 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 152662 (NESB).

Description. Male. Body length: 2.48 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head almost as long as wide (Figure 1C); mandible with two apical teeth, base narrower than apex; median clypeal lobe trapezoidal, with two apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest strongly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4B), depression shallow, drop-shaped and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit large, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6E), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 6F), simple, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe very short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet burotuensis refers to Burotu, described by Fijian people as the most delightful place and a residence of the gods.

Differential diagnosis. This species is similar to D. abaiae sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. wetliva from Indonesia by having the hypostomal carina without teeth, and metasomal segment II with the lateral tergal process bearing the depression small and shallow. However, D. burotuensis sp. nov. has the harpe strongly curved laterad, and the aedeagal dorsal valves progressively narrowing apicad, whereas D. wetliva has the harpe slightly curved laterad, and the aedeagal dorsal valves entirely wide.

Distribution. Fiji (Kadavu and Taveuni Islands).

 

Dissomphalus cagawalui Nunes, Azevedo & Colombo sp. nov.

Figure 1D, Figure 4C and Figure 6G,H

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 14–21.XI.2002, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164275 (NESB)”. Paratypes: FIJI, same data as holotype except: 1 male, 27.XII.2002–3.I.2003, FBA 146440 (NESB); 2 males, 3–20.XII.2002, FBA 166354, 166355 (NESB); 1 male, Vanua Levu, Bua Prov., Batiqere Range, 6 km NW Killaka Village, 61 m, 10–24.VI.2004, Malaise 3., Schlinger, Tokota’a., 16.811° S, 178.988° E, FBA 164936 (NESB).

Description. Male. Body length: 2.64 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 1D); mandible with two apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with one rounded very large apical tooth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4C), depression with very excavated, subcircular and large, anterior margin without setae, posterior margin without setae, outer margin with row long setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, with one short setae. Genitalia: Harpe with dorsal margin entirely wide and sinuous (Figure 6G), shorter than gonostipes, apical margin outcurved, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve, bifid, wide (Figure 6H), abruptly narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin angled, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet cagawalui refers to Cagawalu, the Fijian god of war from the island of Bau.

Differential diagnosis. This species is similar to D. daucinai sp. nov. by having the trapezoidal median clypeal lobe, the metasomal segment II with the lateral tergal process, and the aedeagal apex directed paralleled. However, D. cagawalui sp. nov. has the mandibles with two apical teeth, the tergal process with a small tubercle, and the dorsal margin of the harpe entirely wide, whereas D. daucinai sp. nov. has the mandibles with four apical teeth, the tergal process without a tubercle, and the dorsal margin of the harpe wide only basally.

Comparison with Oceanian congeners. This species is similar to D. kukamba Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with two apical teeth, and the metasomal segment II with lateral tergal process. However, D. cagawalui sp. nov. has the tergal process with the depression large and very excavated, and the aedeagal ventral valves abruptly narrowing apicad, whereas D. kukamba has the tergal process without depression, and the aedeagal ventral valves progressively narrowing apicad.

Distribution. Fiji (Taveuni and Viti Levu Islands).

 

Dissomphalus dakuwaqai Nunes, Azevedo & Colombo sp. nov.

Figure 1E, Figure 4D and Figure 6I,J

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Type material. Holotype: male labeled: “FIJI, Viti Levu, Vude Prov., Koroyanitu Pk., 1 km E Abaca Vlg., 800 m, 22.IV–6.V.03, Malaise 1, coll. Schlinger, Tokota’a., 17.667° S, 177.55° E, FBA 175421 (NESB)”. Paratypes: FIJI, 3 males, Kadavu I, 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary., 60 m, 7.III–11.IV.04, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 173808,173818,173832 (NESB); 1 male, 9–30.V.2003, FBA 166002 (NESB); 1 male, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 14–21.XI.2002, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164259 (NESB); 3 males, 3–20.XII.2002, FBA 166347, 166349, 166350 (NESB); 1 male, Viti Levu, Nadarivatu, 850 m, 8–13.III.1963, C.M.Yoshimoto, Collector, (BPBM); 1 male, same data as holotype except: FBA 175424 (NESB).

Description. Male. Body length: 2.84 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 1E); mandible with three apical teeth, base narrower than apex; median clypeal lobe subtrapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest strongly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with sublateral tergal process (Figure 4D), depression shallow, subcircular and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, without tubercle, pit large, with short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6I), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 6J), simple, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe very short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Variations. The mandible may have three apical teeth, as in the holotype, or four apical teeth in some paratypes.

Etymology. The specific epithet dakuwaqai refers to Dakuwaqa, the Fijian god of the sea.

Differential diagnosis. This species is similar to D. vulavula sp. nov. by having the mandibles with three apical teeth, the tridentate clypeus, and the metasomal segment II with the sublateral tergal process. However, D. dakuwaqai sp. nov. has the aedeagal ventral valvae with the apex positioned anterior to the apex of dorsal valve, the bifid ventral valve, and the smooth aedeagal outer lobe, whereas D. vulavula sp. nov. has the aedeagal ventral valve with the apex aligned with the dorsal valve, the simple ventral valve, and the crenulate aedeagal outer lobes.

Comparison with Oceanian congeners. This species is similar to D. taun from Indonesia by having the mandibles with three apical teeth, and the metasomal segment II with lateral tergal process with depression shallow. However, D. dakuwaqai sp. nov. has the tergal process without tubercles and the margins of depressions without setae, and the aedeagal dorsal valves progressively narrowing apicad, whereas D. taun has the tergal process with tubercles and the margins of depressions with very long setae, and the aedeagal dorsal valves abruptly narrowing apicad.

Distribution. Fiji (Kadavu, Taveuni, and Viti Levu Islands).

 

Dissomphalus daucinai Nunes, Azevedo & Colombo sp. nov.

Figure 1F, Figure 4E and Figure 6K,L

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.6 km SE Tavuki Vlg., Mt. Devo Peak, 1187 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 150858 (NESB)”. Paratypes: FIJI, same data as holotype except: 2 males, FBA 150871, 150857 (NESB); 1 male, Viti Levu, 1.1 km SSW, Volivoli Vlg., Sigatoka Sand Dunes, 55 m, 8.X.–14.XII.2002, Malaise 2, coll. Schlinger, M.Tokota’a., 18.169° S, 177.485° E, FBA 093215 (NESB).

Description. Male. Body length: 3.12 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 1F); mandible with four apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4E), depression very shallow, circular and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6K), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 6L), bifid, wide, abruptly narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe very short, with apical margin angled, and posterad, inner pair membranous and setose; aedeagal apodeme extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet daucinai refers to Daucina, the god of seafaring Fiji.

Differential diagnosis. This species is similar to D. cagawalui sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. kukamba from Papua New Guinea by having the metasomal segment II with lateral tergal process with tubercles small, and the aedeagal ventral valves with apex bifid. However, D. daucinai sp. nov. has the mandibles with three apical teeth, and the median clypeal lobe well-defined, whereas D. kukamba has the mandibles with two apical teeth, and the median clypeal lobe ill-defined.

Distribution. Fiji (Taveuni, and Viti Levu Islands).

 

Dissomphalus degeii Nunes, Azevedo & Colombo sp. nov.

Figure 1G, Figure 4F and Figure 6M,N

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 30.VI–31.VII.04. Malaise 3 coll. Schlinger, M. Tokota’a. 16.841° S, 179.968° W. FBA 148609 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I, 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary., 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166010 (NESB); 1 male, same data as holotype except: 3–20.XII.2002, FBA 166362 (NESB); 1 male, Des Vocux Peak, 900 m, 16 July 1987, Monteith & Cook Pyrethrum/Tree trunks (QMSB).

Description. Male. Body length: 2.71 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 1G); mandible with three apical teeth, base as wide as apex; median clypeal lobe subtrapezoidal, with one sharpened apical tooth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 4F), depression shallow, drop-shaped and large, anterior margin without setae, posterior margin without setae, outer margin with row long setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6M), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin serrated; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 6N), slightly bifid, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet degeii refers to Degei, the supreme Fijian god and the creator of the (Fijian) world.

Differential diagnosis. This species is similar to D. kava sp. nov. by having the mandibles with three apical teeth, the median clypeal lobe with one sharpened apical tooth, the metasomal segment II with the lateral tergal process, and the harpe almost as long as the gonostipes. However, D. degeii sp. nov. has the subtrapezoidal median clypeal lobe, the digitus with a serrated dorsal margin, the volsellar apex positioned anterior to the aedeagal apex, and the simple ventral valvae, whereas D. kava sp. nov. has the trapezoidal median clypeal lobe, the digitus with a smooth dorsal margin, the volsellar apex aligned with the aedeagal apex, and the bifid ventral valvae.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Fiji (Kadavu and Taveuni Islands).

 

Dissomphalus kakamora Nunes, Azevedo & Colombo sp. nov.

Figure 1H, Figure 4G and Figure 6O,P

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Type material. Holotype: male labeled: “SOLOMON IS., New Georgia: Munda, 0–200 m. XI.1975. N.H.L Krauss Collector Bishop Museum, (BPBM)”. Paratype: SOLOMON IS., 1 male, Florida Is., Nggela I., Haleta, 250 m, 17.X.1964, R. Straatman, Malaise Trap, BISHOP, (BPBM).

Description. Male. Body length: 2.29 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 1H); mandible with two apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4G), depression shallow, circular and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with large tubercle, low, placed on center of depression, pit large, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 6O), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 6P), slightly bifid, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin rounded, and posterad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet kakamora refers to Kakamora, a mythical population of elf-like creatures in the tradition of the Solomon Islands.

Differential diagnosis. This species is similar to D. takeii sp. nov. by having the metasomal segment II with the lateral tergal process, the harpe longer than the gonostipes, and the aedeagal dorsal lobe with the outer pair stout and coarse. However, D. kakamora sp. nov. has the mandible with two apical teeth, the tergal process with the depression with the outer margin with a few long setae, and the aedeagal apex curved laterad, whereas D. takeii sp. nov. has the mandible with three apical teeth, the tergal process with the depression with the outer margin without setae, and the aedeagal apex parallel.

Comparison with Oceanian congeners. This species is similar to D. switbiskit Mugrabi & Azevedo, 2016 from Papua New Guinea by having the metasomal segment II with lateral tergal process with tubercles large, and the dorsal margin of harpe wide basally. However, D. kakamora sp. nov. has the mandibles with two apical teeth, and the bifid apex of the aedeagal dorsal valves aligned with the apex of the aedeagal ventral valves, whereas D. switbiskit has the mandibles with four apical teeth, and the simple apex of the aedeagal dorsal valves anterior to the apex of the aedeagal ventral valves.

Distribution. Solomon Islands (Florida and New Georgia Islands).

 

Dissomphalus kauvadra Nunes, Azevedo & Colombo sp. nov.

Figure 1I, Figure 4H and Figure 7A,B

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Type material. Holotype: male labeled: “FIJI, Viti Levu, Naitasiri Prov., 1.8 km E Navali Vlg. 700 m, old tr1, to Mt. Tomaniivi. 9–20.XIII.2003, Malaise 4, Schlinger, Tokota’a., 17.621° S, 177.998° E, FBA 173155 (NESB)”. Paratype: FIJI, 1 male, same data as holotype except: FBA 173134 (NESB).

Description. Male. Body length: 2.68 mm. Color: Head, mesosoma and metasoma black. Head: Head wider than long (Figure 1I); mandible with two apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4H), depression deep, circular and large, anterior margin without setae, posterior margin without setae, outer margin with few short setae, inner margin without setae, with large tubercle, low, placed on center of depression, pit small, with very short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7A), longer than gonostipes, apical margin sinuous, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 7B), simple, wide, progressively narrowing apicad, curved mesad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose, outer pair stout, coarse and with projections; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet kauvadra is a noun in apposition and refers to Kauvadra, a sacred mountain in Fijian tradition.

Differential diagnosis. This species is similar to D. madrali sp. nov. by having the median clypeal lobe with three apical teeth, the metasomal segment II with the lateral tergal process, and the aedeagal outer lobes short. However, D. kauvadra sp. nov. has the mandible with two apical teeth, the median clypeal lobe trapezoidal, the harpe almost as long as the gonostipes, and the aedeagal outer pair smooth, whereas D. madrali sp. nov. has the mandible with four apical teeth, the median clypeal lobe subtrapezoidal, the harpe longer than the gonostipes, and the aedeagal outer pair crenulate.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Fiji (Viti Levu Island).

 

Dissomphalus kava Nunes, Azevedo & Colombo sp. nov.

Figure 2A, Figure 4I and Figure 7C,D

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Type material. Holotype: male labeled: “FIJI, Viti Levu., 1.1 km SSW, Volivoli Vlg., Sigatoka Sand Dunes, 55 m, 8.X.–14.XII.2002, Malaise 2, coll. Schlinger, M. Tokota’a., 18.169° S, 177.485° E, FBA 093214 (NESB)”. Paratypes: FIJI, 1 male, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 31.X–14.XI.02, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 149399 (NESB); 1 male, 30.VI–31.VII.04, FBA 148618 (NESB); 1 male, 892 m, 14–31.VII.2004, Malaise 4, 16.837 ºS, 179.973 ºW, FBA 151754 (NESB); 5 males, Mt. Devo Peak, 1188 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 150850, 150875, 152657, 152661, 152666 (NESB); 1 male, Viti Levu, Vuda Prov. 1 km SW Vaturu Dam, 620 m, 2–14.VII.2004, Malaise 5, coll. E.I. Schlinger, Tokota’a., 17.754° S, 177.665° E, FBA 175905 (NESB).

Description. Male. Body length: 2.71 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head almost as long as wide (Figure 2A); mandible with three apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with one sharpened apical tooth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4I), without depression, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with small tubercle, low, pit small, with short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7C), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 7D), bifid, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet kava is a noun in apposition and refers to Kava, a sacred Fijian drink offered to a host of invoked gods.

Differential diagnosis. This species is similar to D. degeii sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. mwalo Mugrabi & Azevedo, 2016 from Papua New Guinea by having the median clypeal lobe with one sharpened apical tooth, the metasomal segment II with lateral tergal process without depressions, and the aedeagal dorsal valves with apex bifid. However, D. kava sp. nov. has the mandibles with three apical teeth, and the apex of the aedeagal dorsal valves without projection, whereas D. mwalo has the mandibles with four apical teeth, and the apex of the aedeagal dorsal valves with short and crenulate projection.

Distribution. Fiji (Taveuni, and Viti Levu Islands).

 

Dissomphalus madrali Nunes, Azevedo & Colombo sp. nov.

Figure 2B, Figure 4J and Figure 7E,F

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Type material. Holotype: male labeled: “FIJI, Viti Levu, Vuda Prov., 1 km SW Vaturu Dam, 620 m 2–14.VII.2004, Malaise 3, coll. E.I Schlinger, Tokota’a. 17.754° S, 177.665° E. FBA 175904 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I, 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary., 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166001 (NESB); 1 male, 7.III–11.IV.04, FBA 166014 (NESB); 2 males, Viti Levu, 1.1 km SSW, Volivoli Vlg, Sigatoka Sand Dunes, 55 m, 8.X.–14.XII.2002, Malaise 2, coll. Schlinger, M. Tokota’a., 18.169 S, 177.485 E., FBA 093207, 093209 (NESB).

Description. Male. Body length: 4.06 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 2B); mandible with four apical teeth, base as wide as apex; median clypeal lobe subtrapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4J), depression deep, drop-shaped and large, anterior margin without setae, posterior margin without setae, outer margin with row long setae, inner margin without setae, with large tubercle, low, placed on center of depression, pit large, with short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7E), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 7F), simple, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin rounded, crenulate, and posterad, inner pair membranous and setose, outer pair stout, coarse and with projections; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet madrali is a noun in apposition and refers to madrali, the Fijian religious act of offering.

Differential diagnosis. This species is similar to D. kauvadra sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. abababa Mugrabi & Azevedo, 2016 from Papua New Guinea by having the metasomal segment II with lateral tergal process, the aedeagal dorsal valves with apex aligned with the apex of aedeagal ventral valves, and the aedeagal outer lobes with projections. However, D. madrali sp. nov. has the mandibles with four apical teeth, and the tergal process with deep depressions, whereas D. abababa has the mandibles with three apical teeth, and the tergal process with shallow depressions.

Distribution. Fiji (Kadavu and Viti Levu Islands).

 

Dissomphalus meke Nunes, Azevedo & Colombo sp. nov.

Figure 2C, Figure 4K and Figure 7G,H

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Type material. Holotype: male labeled: “FIJI, Viti Levu, Lami, 0–200 m II.1977 N.L.H Krauss, Coll. BISHOP MUSEUM. Acc. No. 1977.81, (BPBM)”.

Description. Male. Body length: 2.38 mm. Color: Head and mesosoma dark castaneous, metasoma castaneous. Head: Head as long as wide (Figure 2C); mandible with three apical teeth, base narrower than apex; median clypeal lobe subtrapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 4K), depression deep, drop-shaped and large, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, with small tubercle, low, placed on posterior area of depression, pit large, with short, dense tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7G), longer than gonostipes, apical margin sinuous, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex posterior to dorsal valve (Figure 7H), bifid, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet meke is a noun in apposition and refers to meke, the Fijian religious chanting practiced as a mode of pacifying the gods.

Differential diagnosis. This species is similar to D. musukau sp. nov. by having the head as long as wide, the metasomal segment II with the lateral tergal process, and the outer lobes apex ventrad. However, D. meke sp. nov. has the mandible with three apical teeth, the median clypeal lobe subtrapezoidal with three apical teeth, and the aedeagal ventral valvae bifid, whereas D. musukau sp. nov. has the mandible with four apical teeth, the ill-defined median clypeal lobe with one apical tooth, and the aedeagal ventral valvae simple.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Fiji (Viti Levu Island).

 

Dissomphalus musukau Nunes, Azevedo & Colombo sp. nov.

Figure 2D, Figure 4L and Figure 7I,J

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.5 km SE Tavuki Vlg., Mt. Devo Peak, 1188 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 152664 (NESB)”.

Description. Male. Body length: 2.65 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 2D); mandible with four apical teeth, base narrower than apex; median clypeal lobe ill-defined, with one sharpened apical tooth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 4L), depression very shallow, subcircular and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7I), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex posterior to dorsal valve (Figure 7J), simple, wide, abruptly narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet musukau is a noun in apposition and refers to musukau, the Fijian religious act of a covenant or solemn vow.

Differential diagnosis. This species is similar to D. rokolai sp. nov. by having the mandible with four apical teeth, the median clypeal lobe with one sharpened tooth, and the metasomal segment II with the lateral tergal process. However, D. musukau sp. nov. has the median clypeal lobe ill-defined and the tergal process with a large depression, whereas D. rokolai sp. nov. has the median clypeal lobe trapezoidal and the tergal process with a small depression.

Comparison with Oceanian congeners. This species is similar to D. hama Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with four apical teeth, the median clypeal lobe ill-defined, and the metasomal segment II with lateral tergal process. However, D. musukau sp. nov. has the tergal process with very shallow, small and circular depressions, and the aedeagal ventral valves with the apex anterior to the apex of aedeagal dorsal valves, whereas D. hama has the tergal process with deep, large and longitudinally elliptical depressions, and the aedeagal ventral valves with apex posterior to the apex of aedeagal dorsal valves.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus naivukii Nunes, Azevedo & Colombo sp. nov.

Figure 2E, Figure 5A and Figure 7K,L

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Type material. Holotype: male labeled: “FIJI, Viti Levu, ECZimmerman Collector, Beating Shrubbery, Mt. Victoria Tholo North IX-13–1938, 3000–4000 m (BPBM)”.

Description. Male. Body length: 2.41 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 2E); mandible with three apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 5A), depression shallow, circular, and small, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7K), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 7L), simple, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet naivukii refers to Nai-vuki, the Fijian mischievous god.

Differential diagnosis. This species is similar to D. nanganangae sp. nov. by having the median clypeal lobe tridentate, the mandible with three apical teeth, and the metasomal segment II with the lateral tergal process. However, D. naivukii sp. nov. has the tubercle of the tergal process with a small pit, the aedeagal ventral valvae simple with the main area wide, progressively narrowing apicad, whereas D. nanganangae sp. nov. has the tubercle of the tergal process without a pit, the aedeagal ventral valvae bifid with the main area wide, abruptly narrowing apicad.

Comparison with Oceanian congeners. This species is similar to D. muli Mugrabi & Azevedo, 2016 from Indonesia by having the mandibles with three apical teeth, and the metasomal segment II with lateral tergal process with shallow and circular depressions. However, D. naivukii sp. nov. has the median clypeal lobe tridentate, and the aedeagal ventral valves with the apex aligned to the apex of aedeagal dorsal valves, whereas D. muli has the median clypeal lobe subtrapezoidal, and the aedeagal ventral valves with the apex anterior to the apex of aedeagal dorsal valves.

Distribution. Fiji (Viti Levu Island).

 

Dissomphalus nanganangae Nunes, Azevedo & Colombo sp. nov.

Figure 2F, Figure 5B and Figure 7M,N

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.6 km SE Tavuki Vlg., Mt. Devo Peak, 1187 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 150866 (NESB)”. Paratypes: FIJI, 1 male, 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 2–10.X.2002, Malaise 3, coll. E.I. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164691 (NESB); 1 male, 31.X–14.XI.02, FBA 149398 (NESB); 2 males, Mt. Devo, 892 m, 14–31.VII.2004, Malaise 4, coll. E. I. Schlinger, M. Tokota’a., 16.837° S, 179.973° W, FBA 151756, 151762 (NESB).

Description. Male. Body length: 2.45 mm. Color: Head black, mesosoma dark castaneous and metasoma castaneous. Head: Head as long as wide (Figure 2F); mandible with three apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 5B), without depression, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with very small tubercle, low, pit very small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 7M), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 7N), bifid, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, crenulate, and mesad, inner pair membranous and setose, outer pair stout, coarse and with projections; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet nanganangae refers to Nangananga, the Fijian goddess presiding over the realm of the dead.

Differential diagnosis. This species is similar to D. naivukii sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. papai Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with three apical teeth, the aedeagal dorsal valves with apex with projections, and aedeagal ventral valves with apex bifid. However, D. nanganangae sp. nov. has the tergal process without depressions and with very small tubercles, and aedeagal dorsal valves aligned with aedeagal ventral valves, whereas D. muli has the tergal process with depressions and with large tubercles, and aedeagal dorsal valves posterior with aedeagal ventral valves.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus naqaii Nunes, Azevedo & Colombo sp. nov.

Figure 2G and Figure 7O,P

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.5 km SE Tavuki Vlg., Devo Peak, 1188 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota ‘a. 16.843° S, 179.968° W. FBA 152663 (NESB)”. Paratypes: FIJI, 1 male, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 2–10.X.2002, Malaise 3, coll. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164683 (NESB); 1 male, 14–21.XI.2002, FBA 164261 (NESB); 1 male, 21.XI–13.XII.02 FBA 164762 (NESB); 1 male, 3–20.XII.2002, FBA 166368 (NESB); 1 male, 27.XII.2002–3.I.2003, FBA 146439 (NESB); 1 male, 892 m, 14–31.VII.2004; 1 male, same data as holotype except: 5.6 km SE, 1187 m, 21.XI–13.XII.02, 16.843° S, 179.966° W, FBA 149710 (NESB).

Description. Male. Body length: 3.51 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 2G); mandible with two apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II without tergal process. Genitalia: Harpe with dorsal margin wide basally (Figure 7O), longer than gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex posterior to dorsal valve (Figure 7P), simple, wide, abruptly narrowing apicad, curved mesad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose, outer pair stout, coarse and with projections; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet naqaii refers to Naqai, the Fijian messenger god.

Differential diagnosis. This species is similar to D. bului sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus nganivatu Nunes, Azevedo & Colombo sp. nov.

Figure 2H and Figure 8A,B

urn:lsid:zoobank.org:act:02D86007-6C21-4F0C-B40E-CBCD2D6696E4

Type material. Holotype: male labeled: “FIJI, Vanua Levu, Bua Prov., Batigere Range, 6 km NW Kilala Village, 61 m, 10–24.VI.2004, Malaise 3. Schlinger, Tokota’a. 16.811° S, 178.988° E. FBA 164931 (NESB)”. Paratypes: FIJI, 1 male, Taveuni, Cakaudrove Prov., Tavuki Vlg., Mt. Devo, 892 m, 14–31.VII.2004, Malaise 34, coll. Schlinger, M. Tokota’a., 16.837° S, 179.973° W, FBA 151743 (NESB); FIJI, same data as holotype except: 1 male, 164930 (NESB).

Description. Male. Body length: 1.56 mm. Color: Head, mesosoma and metasoma light castaneous. Head: Head as long as wide (Figure 2H); mandible with three apical teeth, base narrower than apex; median clypeal lobe subtrapezoidal, with one rounded very short apical tooth, straight in dorsal view; median clypeal carina low in profile, angled; frons strongly coriaceous, punctures small; vertex crest strongly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II without tergal process. Genitalia: Harpe with dorsal margin wide basally (Figure 8A), longer than gonostipes, apical margin sinuous, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 8B), simple, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet nganivatu is a noun in apposition and refers to Ngani-vatu, a gigantic bird from Fijian folklore.

Differential diagnosis. This species is different from all congeners by having the head as long as wide, the mandibular base narrower than the mandibular apex, the metasomal segment II without the tergal process, and the aedeagal ventral valvae with the apical margin parallel.

Comparison with Oceanian congeners. This species is similar to D. bisket Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with three apical teeth, the median clypeal tooth rounded, and the metasomal segment II without tergal process. However, D. nganivatu sp. nov. has the aedeagal dorsal valves with apex posterior to the apex of aedeagal ventral valves, and without projections, whereas D. bisket has the aedeagal dorsal valves with apex aligned to the apex of aedeagal ventral valves, and with triangular projections.

Distribution. Fiji (Vanua Levu Island).

 

Dissomphalus qiqi Nunes, Azevedo & Colombo sp. nov.

Figure 2I, Figure 5C and Figure 8C,D

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Type material. Holotype: male labeled: “FIJI: Taveuni, Cakaudrove Prov. 5.3 km SE Tavuki Vlg., Mt. Devo 1064 m, 2–10.X.2002, Malaise 3, coll. E.I. Schlinger, M. Tokota’a, 15.841° S, 179.968° W, FBA 154573 (NESB)”.

Description. Male. Body length: 3.23 mm. Color: Head and mesosoma black, metasoma light castaneous. Head: Head as long as wide (Figure 2I); mandible with four apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with three teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons weakly coriaceous, punctures very small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5C), depression deep, subcircular and large, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with large tubercle, low, placed on center of depression, pit small. Genitalia: Harpe with dorsal margin wide basally (Figure 8C), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin serrated; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 8D), bifid, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose, outer pair stout and coarse; aedeagal apodeme extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet qiqi is a noun in apposition and refers to qiqi, one of the smallest Fijian birds, believed to have landed to weep over the flooded land during a time of deluge.

Differential diagnosis. This species is similar to D. madrali sp. nov. by having the medial clypeal lobe with three apical teeth, the mandible with four apical teeth, and the tergal process with a large depression and a large tubercle. However, D. qiqi sp. nov. has the head almost as long as wide, the harpe almost as long as the gonostipes, the aedeagal ventral valvae with the apex bifid, and the aedeagal outer pair without projections, whereas D. madrali sp. nov. has the head longer than wide, the harpe longer than the gonostipes, the aedeagal ventral valvae entirely simple, and the aedeagal outer pair with projections.

Comparison with Oceanian congeners. This species is similar to D. susu Mugrabi & Azevedo, 2016 from Indonesia by having the mandibles with four apical teeth, the median clypeal carina straight in profile, the metasomal segment II with lateral tergal process with deep depressions, and the aedeagal ventral valves with apex bifid. However, D. qiqi sp. nov. has the tergal process with subcircular depressions, without setae, and the aedeagal ventral valves with apex without projections, whereas D. susu has the tergal process with longitudinally elliptical depressions, with small and long setae on anterior and lateral areas, and the aedeagal ventral valves with apex with digitiform projections.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus rakomokoi Nunes, Azevedo & Colombo sp. nov.

Figure 3A, Figure 5D and Figure 8E,F

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 14–21.XI.2002, Malaise 3, Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164260 (NESB)”. Paratype: FIJI, 1 male, same data as holotype except: 5.5 km SE Tavuki Vlg., Mt. Devo Peak, 1187 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M. Tokota’a., 16.843° S, 179.966° W, FBA 152660 (NESB).

Description. Male. Body length: 3.57 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 3A); mandible with four apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with three apical teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5D), without depression, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, without tubercle, pit small, with very short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 8E), almost as long as gonostipes, apical margin sinuous, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 8F), simple, wide, progressively narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet rakomokoi refers to Rakomoko, the Fijian assassin god.

Differential diagnosis. This species is similar to D. saumakii sp. nov. by having the mandible with four apical teeth, the median clypeal lobe with three apical teeth, the metasomal segment II with the lateral tergal process, and the aedeagal outer lobes short. However, D. rakomokoi sp. nov. has the head as long as wide and the aedeagal ventral valvae apex curved laterad, whereas D. saumakii sp. nov. has the head longer than wide and the ventral valvae apex slightly curved mesad.

Comparison with Oceanian congeners. This species is similar to D. anien Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with four apical teeth, metasomal segment II with lateral tergal process, and the aedeagal dorsal valves with apex posterior to apex of aedeagal ventral valves. However, D. rakomokoi sp. nov. has the tergal process without depressions, and the aedeagal ventral valves with apex without projections, whereas D. anien has the tergal process with deep and subcircular depressions, and the aedeagal ventral valves with apex with projections.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus ratumaibului Nunes, Azevedo & Colombo sp. nov.

Figure 3B, Figure 5E and Figure 8G,H

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Type material. Holotype: male labeled: “FIJI, Kadavu I., 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary., 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166011 (NESB)”. Paratypes: FIJI, same data as holotype except: 5 males, FBA 166007, 166012, 166013, 166015, 166016; 1 male, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 24–31.X.2002, Malaise 3, coll. E.I. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164979 (NESB); 3 males, 31.X–14.XI.02, FBA 149403, 149404, 149405 (NESB); 2 males, 892 m, 14–31.VII.2004, Malaise 4, 16.837° S, 179.973° W, FBA 151750, 151760 (NESB); 8 males, 5.6 km SE Tavuki Vlg., Mt. Devo Peak, 1187 m, 30.VI–14.VIII.2004, Malaise 1, 16.843° S, 179.966° W, FBA 150852, 150856, 150861, 150865, 150867, 150868, 150869, 150874 (NESB).

Description. Male. Body length: 2.87 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 3B); mandible with five apical teeth, base narrower than apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with lateral tergal process (Figure 5E), depression very shallow, subcircular and small, anterior margin with few long setae, posterior margin without setae, outer margin with row long setae, inner margin without setae, with very small tubercle, low, placed on center of depression, pit very small, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 8G), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 8H), bifid, wide, abruptly narrowing apicad, curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad or mesad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet ratumaibului refers to Ratumaibulu, the Fijian god of agriculture and fertility.

Differential diagnosis. This species is similar to D. umaroai sp. nov. by having the mandibles with five apical teeth and the metasomal segment II with the lateral tergal process. However, D. ratumaibului sp. nov. has the median clypeal lobe tridentate, the harpe almost as long as the gonostipes, the volsellar apex anterior to the aedeagal apex, and the ventral valvae apex curved laterad, whereas D. umaroai sp. nov. has the median clypeal lobe trapezoidal, the harpe longer than the gonostipes, the volsellar apex aligned with the aedeagal apex, and the ventral valvae apex slightly curved mesad.

Comparison with Oceanian congeners. This species is similar to D. aiskrim Mugrabi & Azevedo, 2016 from Papua New Guinea by having the metasomal segment II with lateral tergal process with shallow depressions, and the aedeagal ventral valves with apex bifid. However, D. ratumaibului sp. nov. has the mandibles with five apical teeth, the tergal process tubercles glabrous, and the aedeagal dorsal valves with apex posterior to the apex of aedeagal ventral valves, whereas D. anien has the mandibles with four apical teeth, the tergal process tubercles setose, and the aedeagal dorsal valves with apex anterior to the apex of aedeagal ventral valves.

Distribution. Fiji (Kadavu and Taveuni Islands).

 

Dissomphalus ravuvui Nunes, Azevedo & Colombo sp. nov.

Figure 3C and Figure 8I,J

urn:lsid:zoobank.org:act:FB712C12-536A-48F5-AA2F-A31C0DBA769C

Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.6 km SE Tavuki Vlg., Devo Peak, 1187 m, 30.VI–14.VIII.2004, Malaise 1, Schlinger, M.tokota’a.16.843° S, 179.966° W. FBA 150876 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I., 0.25 km SW, Solodamu Vlg, Moanakaka Bird Sanctuary., 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166019 (NESB); 3 males, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 2–10.X.2002, Malaise 3, coll. E.I. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164689, 164692, 164693 (NESB); 1 male, 31.X–14.XI.02, FBA 149369 (NESB); 1 male, 21.XI–13.XII.02, 164761 (NESB); 1 male, 3–20.XII.2002, FBA 166365 (NESB); 1 male, 27.XII.2002–3.I.2003, FBA 146437 (NESB); 10 males, 30.VI–31.VII.04, FBA 148607, 148612, 148613, 148614, 148615, 148616, 148617, 148620, 148621, 148623; 2 males, 892 m, 14–31.VII.2004, Malaise 4, coll. E. I. Schlinger, M. Tokota’a., 16.837° S, 179.973° W, FBA 151751, 151763 (NESB); 1 male, same data as holotype except: FBA 150872; 1 male, Viti Levu, 1.1 km SSW, Volivoli Vlg., Sigatoka Sand Dunes, 55 m, 8.X.–14.XII.2002, Malaise 2, coll. Schlinger, M. Tokota’a., 18.169 S, 177.485 E., FBA 093225 (NESB).

Description. Male. Body length: 3.52 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head wider than long (Figure 3C); mandible with four apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with one sharpened apical tooth, straight in dorsal view; median clypeal carina low in profile, angled; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II without tergal process. Genitalia: Harpe with dorsal margin wide basally (Figure 8I), almost as long as gonostipes, apical margin sinuous, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 8J), simple, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin rounded, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet ravuvui refers to Ravuvu, the Fijian jealous god.

Differential diagnosis. This species is similar to D. rogovoka sp. nov. by having the median clypeal lobe trapezoidal and the metasomal segment II without the tergal process. However, D. ravuvui sp. nov. has the median clypeal lobe with one apical sharpened tooth, and the outer aedeagal lobe short, whereas D. rogovoka sp. nov. has the median clypeal lobe with three apical rounded teeth, and the outer aedeagal lobe long.

Comparison with Oceanian congeners. This species is similar to D. lewa Mugrabi & Azevedo, 2016 from Papua New Guinea by having the median clypeal tooth sharpened, the metasomal segment II without tergal process, and the aedeagal ventral valves with apex simple. However, D. ravuvui sp. nov. has the mandibles with four apical teeth, and the aedeagal dorsal valves with apex posterior to the apex of aedeagal ventral valves, whereas D. lewa has the mandibles with three apical teeth, and the aedeagal dorsal valves with apex anterior to the apex of aedeagal ventral valves.

Distribution. Fiji (Kadavu, Taveuni, and Viti Levu Islands).

 

Dissomphalus rogovoka Nunes, Azevedo & Colombo sp. nov.

Figure 3D and Figure 8K,L

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt Devo, 1064 m, 14–21.XI.2002, Malaise 3, coll. Schlinger, M. Tokota’a. 16.841° S, 179.968° W. FBA 164273 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I., 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary, 60 m, 18.VII–25.VIII.2003, Malaise 4, Schlinger, Tokota’a, 19.078° S, 178.121° E, FBA 147337 (NESB).

Description. Male. Body length: 3.16 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head wider than long (Figure 3D); mandible with three apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with three rounded apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II without tergal process. Genitalia: Harpe with dorsal margin wide basally (Figure 8K), longer than gonostipes, apical margin truncate, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex anterior to apex of dorsal valve (Figure 8L), simple, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet rogovoka refers to Rogovoka, the first boat that brought the first group of ancestors about 3500 years ago.

Differential diagnosis. This species is similar to D. ravuvui sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. lewa Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with three apical teeth, the metasomal segment II without tergal process, and the aedeagal ventral valves with apex simple. However, D. rogovoka sp. nov. has the median clypeal tooth rounded, and the aedeagal dorsal valves with apex posterior to the apex of aedeagal ventral valves, whereas D. lewa has the median clypeal tooth sharpened, and the aedeagal dorsal valves with apex anterior to the apex of aedeagal ventral valves.

Distribution. Fiji (Kadavu and Taveuni Islands).

 

Dissomphalus rokolai Nunes, Azevedo & Colombo sp. nov.

Figure 3E, Figure 5F and Figure 8M,N

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 14–21.XI.2002, Malaise 3, coll. E.I. Schlinger, M. Tokota’a., 16.841° S, 179.968° W, FBA 164270 (NESB)”. Paratypes: FIJI, 1 male, Kadavu I., 0.25 km SW, Solodamu Vlg., Moanakaka Bird Sanctuary., 60 m, 9–30.V.2003, Malaise 4, Schlinger, Tokota’a., 19.078° S, 178.121° E, FBA 166006 (NESB); 1 male, 2–10.X.2002, FBA 164672; 2 males, same data as holotype except: FBA 164262, 164269 (NESB).

Description. Male. Body length: 2.99 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head as long as wide (Figure 3E); mandible with four apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with one sharpened apical tooth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5F), depression shallow, circular and small, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, with large tubercle, high, placed on center of depression, pit large, with short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 8M), almost as long as gonostipes, apical margin outcurved, curved mesad, ventral margin serrated; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 8N), bifid, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet rokolai refers to Rokola, the Fijian carpenter god and first-born of Degei.

Differential diagnosis. This species is similar to D. musukau sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Fiji (Kadavu and Taveuni Islands).

 

Dissomphalus saumakii Nunes, Azevedo & Colombo sp. nov.

Figure 3F, Figure 5G and Figure 8O,P

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt. Devo, 1064 m, 27.XII.2002–3.I.2003. Malaise 3, Schlinger, M. Tokota’a, 16.841° S, 179.968° W FBA 146435 (NESB)”. Paratypes: FIJI, same data as holotype except: 2 males, 14–21.XI.2002, FBA 164268, 164271 (NESB).

Description. Male. Body length: 2.87 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head longer than wide (Figure 3F); mandible with four apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5G), depression shallow, subcircular and small, anterior margin without setae, posterior margin without setae, outer margin with few very short setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit, without setae. Genitalia: Harpe with dorsal margin wide basally (Figure 8O), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 8P), simple, wide, progressively narrowing apicad, slightly curved mesad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet saumakii refers to Saumaki, the Fijian god of tribal protection and loyalty.

Differential diagnosis. This species is similar to D. rakomokoi sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. gamtri Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with four apical teeth, the metasomal segment II with lateral tergal process, and the aedeagal ventral valves with apex bifid. However, D. saumakii sp. nov. has the tergal process with shallow depression and small tubercles, and the aedeagal dorsal valves with apex aligned with the apex of aedeagal ventral valves, whereas D. gamtri has the tergal process with deep depression and large tubercles, and the aedeagal dorsal valves with apex posterior with the apex of aedeagal ventral valves.

Distribution. Fiji (Taveuni Island).

 

Dissomphalus takeii Nunes, Azevedo & Colombo sp. nov.

Figure 3G, Figure 5H and Figure 9A,B

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Type material. Holotype: male labeled: “FIJI, Taveuni, Cakaudrove Prov., 5.3 km SE Tavuki Vlg., Mt Devo, 1064 m, 14–21.XI.2002, Malaise 3, coll. Schlinger, M. Tokota’a. 16.841° S, 179.968° W. FBA 164276 (NESB)”. Paratype: FIJI, 1 male, Viti Levu, Nandarivatu, V-’51, N. Krauss (BPBM).

Description. Male. Body length: 2.49 mm. Color: Head and mesosoma black, metasoma dark castaneous. Head: Head almost as long as wide (Figure 3G); mandible with three apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina high in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest weakly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5H), depression shallow, circular and small, anterior margin without setae, posterior margin without setae, outer margin without setae, inner margin without setae, with small tubercle, high, placed on center of depression, pit absent. Genitalia: Harpe with dorsal margin wide basally (Figure 9A), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 9B), simple, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet takeii refers to Takei, the Fijian god who can assume both a very ugly and a very beautiful form.

Differential diagnosis. This species is similar to D. kakamora sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. sanda Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with three apical teeth, the metasomal segment II with lateral tergal process with shallow depressions, and the aedeagal ventral valves with apex simple. However, D. takeii sp. nov. has the median clypeal carina straight or nearly so in profile, and the tergal process with depressions circular and small tubercles, whereas D. sanda has the median clypeal carina convex in profile, and the tergal process with depressions longitudinally elliptical and large tubercles.

Distribution. Fiji (Taveuni and Viti Levu Islands).

 

Dissomphalus umaroai Nunes, Azevedo & Colombo sp. nov.

Figure 3H, Figure 5I and Figure 9C,D

urn:lsid:zoobank.org:act:7F1AD511-E9DB-4EB1-8346-B946DA6F8F83

Type material. Holotype: male labeled: “SOLOMON Is. Guadalcanal, Tambalia, 30 km W. Honiara, 21V.’64 R. Straatman Malaise Trap, BISHOP (BPBM)”.

Description. Male. Body length: 2.58 mm. Color: Head and mesosoma dark castaneous, metasoma castaneous. Head: Head almost as long as wide (Figure 3H); mandible with five apical teeth, base as wide as apex; median clypeal lobe trapezoidal, with one sharpened apical tooth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest straight or nearly so. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina complete. Metasoma: Metasomal segment II with lateral tergal process (Figure 5I), depression shallow, subcircular and large, anterior margin without setae, posterior margin without setae, outer margin with few long setae, inner margin without setae, with small tubercle, low, placed on center of depression, pit large, with short tuft of setae. Genitalia: Harpe with dorsal margin wide basally (Figure 9C), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 9D), simple, wide, progressively narrowing apicad, parallel; aedeagal dorsal valve with two pairs of apical lobes, outer lobe long, with apical margin acute, and ventrad, inner pair membranous and setose; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet umaroai refers to Umaroa, leader of the Muara clan, who saved his people from the great flood Ruarua in Solomon Islands culture.

Differential diagnosis. This species is similar to D. ratumaibului sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is morphologically distinct from all known congeners from Indonesia and Papua New Guinea.

Distribution. Solomon Islands (Guadalcanal Island).

 

Dissomphalus vulavula Nunes, Azevedo & Colombo sp. nov.

Figure 3I, Figure 5J,K and Figure 9E,F

urn:lsid:zoobank.org:act:15366E10-5785-469D-B35E-B7B1CFB0DBD4

Type material. Holotype: male labeled: “FIJI, Kadavu, Mt Korogatule, 300 m, near Matasawalevu, 4–7 July 1987 G. Monteith, Pyrethrum, Logs, Trees, (QMSB)”.

Description. Male. Body length: 2.39 mm. Color: Head black, mesosoma dark castaneous and metasoma light castaneous. Head: Head almost as long as wide (Figure 3I); mandible with three apical teeth, base as wide as apex; median clypeal lobe tridentate, with three apical teeth, straight in dorsal view; median clypeal carina low in profile, straight or nearly so; frons strongly coriaceous, punctures small; vertex crest strongly incurved. Mesosoma: Metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly. Metasoma: Metasomal segment II with sublateral tergal process (Figure 5J,K), depression deep, circular and large, anterior margin with short setae, posterior margin without setae, outer margin without setae, inner margin without setae, without tubercle, pit absent. Genitalia: Harpe with dorsal margin wide basally (Figure 9E), almost as long as gonostipes, apical margin straight, curved mesad, ventral margin smooth; digitus with dorsal margin smooth; aedeagal ventral valve with apex aligned with apex of dorsal valve (Figure 9F), simple, wide, progressively narrowing apicad, slightly curved laterad; aedeagal dorsal valve with two pairs of apical lobes, outer lobe short, with apical margin acute, and ventrad, inner pair membranous and setose, outer pair stout, coarse and with projections; aedeagal apodeme not extending beyond genital ring. Female: Unknown.

Etymology. The specific epithet vulavula is a noun in apposition and refers to Vulavula, sacred bats in the Fijian religion.

Differential diagnosis. This species is similar to D. dakuwaqai sp. nov., as aforementioned in its section differential diagnosis.

Comparison with Oceanian congeners. This species is similar to D. bratasusa Mugrabi & Azevedo, 2016 from Papua New Guinea by having the mandibles with three apical teeth, the metasomal segment II with tergal process, and the aedeagal ventral valves with apex bifid. However, D. vulavula sp. nov. has the tergal process with deep depressions and without tubercles, and the aedeagal dorsal valves with apex aligned with the apex of aedeagal ventral valves, whereas D. bratasusa has the tergal process with shallow depressions and with small tubercles, and the aedeagal dorsal valves with apex posterior with the apex of aedeagal ventral valves.

Distribution. Fiji (Kadavu Island).

3.2. Key for Males from Fiji and the Solomon Islands

1. Metasomal segment II without tergal process …………………………………………… 2

- Metasomal segment II with tergal process (Figure 4A–L and Figure 5A–K) ………………… 6

 

2. Mandible with two apical teeth …………………………………………………………… 3

- Mandible with three or four apical teeth …………………………………………………… 4

 

3. Aedeagal outer lobe long, without projection (Figure 6C) …………… D. bului sp. nov.

- Aedeagal outer lobe short, with projection (Figure 7O) ………………… D. naqaii sp. nov.

 

4. Head as long as wide (Figure 2H); mandibular base narrower than mandibular apex; aedeagal ventral valve with apical margin parallel (Figure 8B) …… D. nganivatu sp. nov.

- Head wider than long (Figure 3C,D); mandibular base as wide as mandibular apex; aedeagal ventral valve with apical margin laterally curved (Figure 8J,L) ………………… 5

 

5. Median clypeal lobe with one apical sharp tooth (Figure 3C); metapectal-propodeal disc with metapostnotal median carina incomplete posteriorly ……………………………………………………………………………… D. ravuvui sp. nov.

- Median clypeal lobe with three apical rounded teeth (Figure 3D); metapectal–propodeal disc with metapostnotal median carina complete ……………… D. rogovoka sp. nov.

 

6. Metasomal segment II with sublateral tergal process (Figure 4D and Figure 5J,K) ……… 7

- Metasomal segment II with lateral tergal process (Figure 4A–C,E–L and Figure 5A–I) …… 8

 

7. Tergal process with small depression, with pit (Figure 4D) ……… D. dakuwaqai sp. nov.

- Tergal process with large depression, without pit (Figure 5J,K) …… D. vulavula sp. nov.

 

8. Mandible with two apical teeth …………………………………………………………… 9

- Mandible with three to five apical teeth ……………………………………………………11

 

9. Median clypeal lobe with three apical teeth (Figure 1A,H,I) …………………………… 10

- Median clypeal lobe with one or two apical teeth (Figure 1C,D,F,G, Figure 2A–F,I and Figure 3A,B,E–H) ……………………………………………………………………………………………… 13

 

10. Tergal process with small tubercle (Figure 4A); harpe shorter than gonostipes (Figure 6A,B) ………………………………………………………………………… D. abaiae sp. nov.

- Tergal process with large tubercle (Figure 4G,H); harpe longer than gonostipes (Figure 6O and Figure 7A) …………………………………………………………………………………… 11

 

11. Head wider than long (Figure 1I); tergal process with large depression, outer margin with row long setae (Figure 4H); aedeagal outer lobe with projections (Figure 7A); aedeagal ventral valve entirely simple (Figure 7B) ………………………… D. kauvadra sp. nov.

- Head as long as wide (Figure 1H); tergal process with small depression, outer margin without setae (Figure 4G); aedeagal outer lobe without projections (Figure 6O); aedeagal ventral valve with apex bifid (Figure 6P) ……………………………… D. kakamora sp. nov.

 

12. Median clypeal lobe with two teeth (Figure 1C); harpe longer than gonostipes (Figure 6E); aedeagal ventral valve entirely simple (Figure 6F) …………… D. burotuensis sp. nov.

- Median clypeal lobe with one rounded very large tooth (Figure 1D); harpe shorter than gonostipes (Figure 6G); aedeagal ventral valve with apex bifid (Figure 6H) ……………………………………………………………………………… D. cagawalui sp. nov.

 

13. Mandible with five apical teeth ………………………………………………………… 14

- Mandible with three or four apical teeth ………………………………………………… 15

 

14. Head longer than wide (Figure 3B); median clypeal lobe with three teeth (Figure 3B); tergal process with small depression (Figure 5E); aedeagal ventral valve with apex bifid (Figure 8H) …………………………………………………………… D. ratumaibului sp. nov.

- Head almost as long as wide (Figure 3H); median clypeal lobe with one sharpened tooth (Figure 3H); tergal process with large depression (Figure 5I); aedeagal ventral valve entirely simple (Figure 9D) ………………………………………………… D. umaroai sp. nov.

 

15. Mandible with three apical teeth ………………………………………………………… 16

- Mandible with four apical teeth …………………………………………………………… 21

 

16. Median clypeal lobe with one apical sharpened tooth (Figure 1G and Figure 2A) ………… 17

- Median clypeal lobe with three teeth (Figure 1F, Figure 2B–F,I and Figure 3A,E–G) ……………… 18

 

17. Head longer than wide (Figure 1G); tergal process with depression (Figure 4F); harpe longer than gonostipes (Figure 6M) ………………………………………… D. degeii sp. nov.

- Head almost as long as wide (Figure 2A); tergal process without depression (Figure 4I); harpe almost as long as gonostipes (Figure 7C) …………………………… D. kava sp. nov.

 

18. Harpe longer than gonostipes (Figure 7G,M); aedeagal ventral valve with apex bifid (Figure 7H,N) ………………………………………………………………………………… 19

- Harpe almost as long as gonostipes (Figure 6K, Figure 7E,I,K, Figure 8C,E,M,O and Figure 9A); aedeagal ventral valve entirely simple (Figure 6L, Figure 7F,J,L, Figure 8D,F,N,P and Figure 9B) …………………… 20

 

19. Tergal process without depression (Figure 4K); aedeagal outer lobe without projections (Figure 7G) ……………………………………………………………… D. meke sp. nov.

- Tergal process with deep depression (Figure 5B); aedeagal outer lobe with projections (Figure 7M) …………………………………………………………… D. nanganangae sp. nov.

 

20. Tergal process with depression, outer margin with few long setae (Figure 5A), tubercle with pit on top (Figure 5A); aedeagal outer lobe long (Figure 7K) …… D. naivukii sp. nov.

- Tergal process with depression, outer margin without setae (Figure 5H), tubercle without pit on top (Figure 5H); aedeagal outer lobe short (Figure 9A) ……… D. takeii sp. nov.

 

21. Tergal process without depression (Figure 5D) …………………… D. rakomokoi sp. nov.

- Tergal process with depression (Figure 4E,J,L and Figure 5C,F,G) …………………………… 22

 

22. Medial clypeal lobe with one apical sharpened tooth (Figure 2D and Figure 3E) ………… 23

- Medial clypeal lobe with three apical teeth (Figure 1F, Figure 2B,I and Figure 3F) ………………… 24

 

23. Tergal process with depression, outer margin without setae, tubercle small (Figure 4L) ……………………………………………………………………………… D. musukau sp. nov.

- Tergal process with depression, outer margin with few long setae, tubercle large (Figure 5F) …………………………………………………………………………… D. rokolai sp. nov.

 

24. Tergal process with small depression and small tubercle (Figure 4E and Figure 5G) …… 25

- Tergal process with large depression and large tubercle (Figure 4J and Figure 5C) ………… 26

 

25. Tergal process with depression, outer margin without setae (Figure 4E); harpe longer than gonostipes (Figure 6K); aedeagal ventral valve with apex bifid (Figure 6L) ……………………………………………………………………………… D. daucinai sp. nov.

- Tergal process with depression, outer margin with few short setae (Figure 5G); harpe almost as long as gonostipes (Figure 8O); aedeagal ventral valve entirely simple (Figure 8P) …………………………………………………………………………… D. saumakii sp. nov.

 

26. Head longer than wide (Figure 2B); harpe longer than gonostipes (Figure 7E); aedeagal outer pair with projections (Figure 7E); aedeagal ventral valve entirely simple (Figure 7F) ……………………………………………………………………………… D. madrali sp. nov.

- Head almost as long as wide (Figure 2I); harpe almost as long as gonostipes (Figure 8C); aedeagal outer pair without projections (Figure 8C); aedeagal ventral valve with apex bifid (Figure 8D) ………………………………………………………………… D. qiqi sp. nov.

4. Discussion

The identification of 27 distinct Dissomphalus species from Fiji and the Solomon Islands represents a substantial advancement in our understanding of Bethylidae diversity in the Oceanian region. This increase, which raises the number of known Oceanian species from 91 to 118, reflects a significant (~29%) expansion of the regional taxonomic inventory. Notably, this is the first documented occurrence of Dissomphalus in these island groups, filling a long-standing biogeographic gap highlighted in previous surveys [8].

The strong sexual dimorphism observed in Dissomphalus makes associating males and females particularly challenging when only one sex is available. In addition, females are rarely collected using Malaise traps, likely due to their apterous condition. Future efforts should include alternative sampling methods and molecular analyses to enable reliable association between sexes and to improve our understanding of species boundaries.

The observed morphological diversity, particularly in male genitalia and the tergal process, further reinforces the taxonomic richness of the genus in insular environments. The tergal process, a key diagnostic feature in Dissomphalus systematics [16,17], was found in 22 of the 27 species, with two main structural patterns emerging. Five species lacked this structure entirely, aligning with the amplus species-group previously identified in the Neotropical region [5] and others in the Afrotropical region [3]. This pattern may indicate a case of morphological convergence or a deeper evolutionary relationship worth exploring.

The most common configuration found was the lateral tergal process, which supports the hypothesis that this morphology is likely ancestral or at least widespread across several biogeographic regions [16]. This structural pattern has been frequently observed, not only in Oceanian taxa, such as those from Papua New Guinea [8], but also in representatives from the Oriental region, including Thailand [16], and in Neotropical and Afrotropical lineages [3,4].

Its recurrence across distant and ecologically diverse regions suggests that the lateral tergal process may represent a plesiomorphic condition within the genus, potentially retained in multiple lineages through evolutionary stasis or as a result of stabilizing selection acting on functionally important traits.

From a functional perspective, the tergal process may be involved in species-specific mating behavior or in mechanical reproductive compatibility, which would explain its conservative evolution across geographically isolated populations. Alternatively, the lateral position of the process could reflect a developmental constraint tied to segmental patterning in the metasoma. In either case, the repeated emergence or persistence of this morphology across phylogenetically and geographically distant Dissomphalus species underscores its potential as a key character for both species delimitation and broader phylogenetic inference. Further comparative studies, particularly those integrating molecular data, will be essential to test whether the lateral tergal process truly represents a shared ancestral state or results from multiple independent origins through parallel evolution.

Additionally, distinct variations in the aedeagus, such as the shape and configuration of dorsal and ventral valvae, played a critical role in species delimitation, consistent with previous studies emphasizing the importance of male genitalia in differentiating Dissomphalus species [4,8,18,19].

The morphological differentiation of the aedeagus, particularly in the shape, articulation, and relative positioning of the dorsal and ventral valvae, proved essential for accurate species delimitation. These structures exhibited species-specific patterns that were often more diagnostic than external morphology, highlighting their taxonomic value. This finding is in line with previous studies that have emphasized male genitalia as one of the most reliable sources of character information in Dissomphalus systematics [3,4,8].

Although this study is based solely on morphological characteristics, future integration of molecular data could significantly enhance species delimitation and phylogenetic inference within Dissomphalus. Molecular analyses, such as DNA barcoding or genomic approaches, would be especially valuable for associating males and females, detecting cryptic species, and testing hypotheses of morphological convergence. Combining morphological and molecular data will provide a more robust framework for understanding evolutionary relationships and the biogeographic history of the genus.

One of the most remarkable findings of this study is the high level of endemism apparent among the Dissomphalus populations from Fiji and the Solomon Islands. Not a single species among the 91 previously described from nearby Papua New Guinea was recovered in our samples, despite the relative geographic proximity and shared ecological conditions. Based on the examination of approximately 151 male specimens, we identified 27 distinct species, yielding a striking ratio of 1 species per 5.6 specimens examined. This high species-to-specimen ratio mirrors patterns observed in other biodiversity-rich regions, with rates of one species per 4.3 individuals from Indonesian and Papua New Guinea [8] and one species per 12.5 specimens from Afrotropical revision [3]. These comparisons highlight not only the taxonomic complexity of Dissomphalus, but also the extraordinary diversity concentrated in relatively limited samples from island systems. The absence of species overlapping with nearby faunas supports the hypothesis of strong faunal compartmentalization across Pacific islands [8], with biogeographic isolation acting as a driver of allopatric speciation and morphological diversification. Together, these findings reinforce the notion that these islands are exceptional reservoirs of endemic and yet-undescribed diversity.

The high level of endemism and species richness observed in Dissomphalus from Fiji and the Solomon Islands underscores the ecological and evolutionary uniqueness of these island systems. Such diversity, concentrated in relatively small and geographically isolated areas, reflects long-term biogeographic isolation and supports the hypothesis of strong faunal compartmentalization across the Pacific. From a conservation standpoint, this pattern raises concerns, as endemic species with restricted distributions are particularly vulnerable to habitat degradation, climate change, and invasive species—threats that are increasingly common on oceanic islands. The discovery of 27 apparently endemic species vi a limited sampling effort highlights both the conservation value of these regions and the likelihood that much of their invertebrate biodiversity remains undocumented. Effective conservation planning should consider this hidden diversity, and future taxonomic surveys will be essential for assessing the full extent of island endemism and vulnerability.

Figure 1. Dissomphalus sp., male head, dorsal view. (A) D. abaiae sp. nov., (B) D. bului sp. nov., (C) D. burotuensis sp. nov., (D) D. cagawalui sp. nov., (E) D. dakuwaqai sp. nov., (F) D. daucinai sp. nov., (G) D. degeii sp. nov., (H) D. kakamora sp. nov., (I) D. kauvadra sp. nov. Scale bars: 100 µm.

Figure 1. Dissomphalus sp., male head, dorsal view. (A) D. abaiae sp. nov., (B) D. bului sp. nov., (C) D. burotuensis sp. nov., (D) D. cagawalui sp. nov., (E) D. dakuwaqai sp. nov., (F) D. daucinai sp. nov., (G) D. degeii sp. nov., (H) D. kakamora sp. nov., (I) D. kauvadra sp. nov. Scale bars: 100 µm.

Figure 2. Dissomphalus sp., male head, dorsal view. (A) D. kava sp. nov., (B) D. madrali sp. nov., (C) D. meke sp. nov., (D) D. musukau sp. nov., (E) D. naivukii sp. nov., (F) D. nanganangae sp. nov., (G) D. naqaii sp. nov., (H) D. nganivatu sp. nov., (I) D. qiqi sp. nov. Scale bars: 100 µm.

Figure 2. Dissomphalus sp., male head, dorsal view. (A) D. kava sp. nov., (B) D. madrali sp. nov., (C) D. meke sp. nov., (D) D. musukau sp. nov., (E) D. naivukii sp. nov., (F) D. nanganangae sp. nov., (G) D. naqaii sp. nov., (H) D. nganivatu sp. nov., (I) D. qiqi sp. nov. Scale bars: 100 µm.

Figure 3. Dissomphalus sp., male head, dorsal view. (A) D. rakomokoi sp. nov., (B) D. ratumaibului sp. nov., (C) D. ravuvui sp. nov., (D) D. rogovoka sp. nov., (E) D. rokolai sp. nov., (F) D. saumakii sp. nov., dorsal view, (G) D. takeii sp. nov., (H) D. umaroai sp. nov., (I) D. vulavula sp. nov. Scale bars: 100 µm.

Figure 3. Dissomphalus sp., male head, dorsal view. (A) D. rakomokoi sp. nov., (B) D. ratumaibului sp. nov., (C) D. ravuvui sp. nov., (D) D. rogovoka sp. nov., (E) D. rokolai sp. nov., (F) D. saumakii sp. nov., dorsal view, (G) D. takeii sp. nov., (H) D. umaroai sp. nov., (I) D. vulavula sp. nov. Scale bars: 100 µm.

Figure 4. Dissomphalus sp., male tergal process, dorsal view. (A) D. abaiae sp. nov., (B) D. burotuensis sp. nov., (C) D. cagawalui sp. nov., (D) D. dakuwaqai sp. nov., (E) D. daucinai sp. nov., (F) D. degeii sp. nov., (G) D. kakamora sp. nov., (H) D. kauvadra sp. nov., (I) D. kava sp. nov., (J) D. madrali sp. nov., (K) D. meke sp. nov., (L) D. musukau sp. nov. Scale bars: 100 µm.

Figure 4. Dissomphalus sp., male tergal process, dorsal view. (A) D. abaiae sp. nov., (B) D. burotuensis sp. nov., (C) D. cagawalui sp. nov., (D) D. dakuwaqai sp. nov., (E) D. daucinai sp. nov., (F) D. degeii sp. nov., (G) D. kakamora sp. nov., (H) D. kauvadra sp. nov., (I) D. kava sp. nov., (J) D. madrali sp. nov., (K) D. meke sp. nov., (L) D. musukau sp. nov. Scale bars: 100 µm.

Figure 5. Dissomphalus sp., male tergal process, dorsal view. (A) D. naivukii sp. nov., (B) D. nanganangae sp. nov., (C) D. qiqi sp. nov., (D) D. rakomokoi sp. nov., (E) D. ratumaibului sp. nov., (F) D. rokolai sp. nov., (G) D. saumakii sp. nov., (H) D. takeii sp. nov., (I) D. umaroai sp. nov., (J,K) D. vulavula sp. nov. Scale bars: 100 µm.

Figure 5. Dissomphalus sp., male tergal process, dorsal view. (A) D. naivukii sp. nov., (B) D. nanganangae sp. nov., (C) D. qiqi sp. nov., (D) D. rakomokoi sp. nov., (E) D. ratumaibului sp. nov., (F) D. rokolai sp. nov., (G) D. saumakii sp. nov., (H) D. takeii sp. nov., (I) D. umaroai sp. nov., (J,K) D. vulavula sp. nov. Scale bars: 100 µm.

Figure 6. Dissomphalus sp., male genitalia. (A,B) D. abaiae sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. bului sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. burotuensis sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. cagawalui sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. dakuwaqai sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. daucinai sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. degeii sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. kakamora sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 6. Dissomphalus sp., male genitalia. (A,B) D. abaiae sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. bului sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. burotuensis sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. cagawalui sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. dakuwaqai sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. daucinai sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. degeii sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. kakamora sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 7. Dissomphalus sp., male genitalia. (A,B) D. kauvadra sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. kava sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. madrali sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. meke sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. musukau sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. naivukii sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. nanganangae sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. naqaii sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 7. Dissomphalus sp., male genitalia. (A,B) D. kauvadra sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. kava sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. madrali sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. meke sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. musukau sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. naivukii sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. nanganangae sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. naqaii sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 8. Dissomphalus sp., male genitalia. (A,B) D. nganivatu sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. qiqi sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. rakomokoi sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. ratumaibului sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. ravuvui sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. rogovoka sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. rokolai sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. saumakii sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 8. Dissomphalus sp., male genitalia. (A,B) D. nganivatu sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. qiqi sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. rakomokoi sp. nov., (E) dorsal view, (F) ventral view, (G,H) D. ratumaibului sp. nov., (G) dorsal view, (H) ventral view, (I,J) D. ravuvui sp. nov., (I) dorsal view, (J) ventral view, (K,L) D. rogovoka sp. nov., (K) dorsal view, (L) ventral view, (M,N) D. rokolai sp. nov., (M) dorsal view, (N) ventral view, (O,P) D. saumakii sp. nov., (O) dorsal view, (P) ventral view. Scale bars: 100 µm.

Figure 9. Dissomphalus sp., male genitalia. (A,B) D. takeii sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. umaroai sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. vulavula sp. nov., (E) dorsal view, (F) ventral view. Scale bars: 100 µm.

Figure 9. Dissomphalus sp., male genitalia. (A,B) D. takeii sp. nov., (A) dorsal view, (B) ventral view, (C,D) D. umaroai sp. nov., (C) dorsal view, (D) ventral view, (E,F) D. vulavula sp. nov., (E) dorsal view, (F) ventral view. Scale bars: 100 µm.