Taxonomy

Benchmarking in taxonomy is viewed both as establishing a specimen as a standard of reference and as a process for optimizing that process. Here, it is founded on vision theory that recognition of specimens, as for all objects, is personal to the observer and is based on stored exemplars (benchmark images) in their memory. A special feature of a holotype as a scientific benchmark is that it has been published with a Linnaean name permanently attached. This concept is generalized to include all specimens published by subsequent taxonomists with that name attached (a labeled specimen knowledge base). As a record of usage, it integrates all published images with a Linnaean name. It promotes an inquiry into processes for the selection of such specimens. In the conventional model of practice, taxonomists categorize specimens using their stored representations of already identified individuals; the process is immediate, acute, and autonomous, but is largely concealed; a specimen may be selected as a benchmark, but its typicality is not revealed. As a remedy, a population model of practice is advocated wherein the basic autonomous visual process is supplemented by objective data about a specimen and the probability of its position within a potential source population. Full article

In Yucatán state, Mexico, Triatoma dimidiata (Latreille, 1811) is the primary vector of Trypanosoma cruzi, the parasite that causes Chagas disease. The vector population presents diverse forms and colorations. Therefore, this study was designed to determine the morphotypes of T. dimidiata based on the taxonomy of the body and external genitalia. Between March 2023 and April 2025, 902 triatomines from 15 municipalities were examined. Three main morphotypes were characterized (I to III). Morphotype II was the most abundant (62.86%) and most distributed in the study area (12 of 15 municipalities), with a notable presence in forests and caves. Morphotypes I and III were found primarily outside houses and in chicken coops. Within the characterized specimens of T. dimidiata sensu lato, morphotype II displays more prominent morphological and structural characteristics. They are smaller compared to morphotypes I and III. In morphotype II, the spiracles are covered by a black spot that extends from the connexival plate to the urosternites. Males had short and robust parameres. The median process of the pygophore is long and slender compared to morphotypes I and III. The female tergite VIII has six sides. The taxonomy should be complemented by a study of the life cycle of each morphotype and analysis of its genome. Full article

The Philippines and the Papuan archipelagos harbor a vast diversity of pygmy grasshoppers, including the pygmy devils of the genera Xistra and Tegotettix, as well as visually similar taxa reviewed in this study. A new tribe, two new genera, a new subgenus, three new species, and 24 new or resurrected taxonomic combinations are proposed in this study. A new colorful wingless genus and species, Almacris alleochroa gen. et sp. nov., is described from Mindanao. Taxonomic reshuffling of the genus Xistra is performed—a new subgenus is described, Tegoxistra subgen. nov., to include X. derijei, X. corniculata, and X. cristifera, while the nominotypical subgenus becomes restricted to X. gogorzae and X. sagittaria. All other species previously assigned to Xistra are herewith moved to Xistrella, resulting in 20 new combinations. The genus Ginixistra gen. nov. (Exanimini)—whose members show remarkable similarity to Fiji-endemic Fijixistra—is described for G. novaeguineae, G. davorkae sp. nov., and G. novaebritanniae sp. nov. from New Guinea and New Britain. The new tribe Xistrellini trib. nov. is established to accommodate Afrosystolederus, Bannatettix, Kanakacris, Phaesticus, Pseudoparatettix, Pseudosystolederus, Pseudoxistrella, Synalibas, Systolederus, Teredorus, and Xistrella. Previous molecular phylogenetic studies have confirmed Xistrellini monophyly and suggested that the ancestor of this tribe may have originated during the Cretaceous period, approximately 127–100 million years ago (mya). Full article

Heliaster has long been considered to comprise seven nominal species of starfish distributed across the Eastern Pacific, from Baja California (Mexico) southward to central Chile. Along the southeastern Pacific coast, three taxa have been traditionally recognized: H. helianthus (Paita, northern Peru, to Concepción, central-southern Chile), H. polybrachius (Mexico to Perú), and H. canopus (Juan Fernández Archipelago and Desventuradas Islands). However, extensive morphological overlap among these forms has cast doubt on the validity of H. canopus, with some authors treating it as a synonym for H. helianthus. To clarify this ambiguity, we applied an integrative framework combining detailed morphometrics, phylogenetic inference from mitochondrial (COI) and nuclear (H3) markers, and two species delimitation approaches (bPTP and ASAP). Our sampling spanned Peru, continental Chile, and the oceanic islands of Juan Fernández and Desventuradas. Variation in ray number and relative arm length among H. helianthus, H. canopus, and H. polybrachius proved allometric, scaling strongly with body diameter rather than indicating discrete species boundaries. Molecular data show >95% sequence similarity across all nominal taxa and recover a single, well-supported clade; bPTP and ASAP likewise support one Heliaster lineage throughout the southeastern Pacific, corresponding to H. helianthus. Accordingly, we redescribe H. helianthus, designate a neotype from Quintay, Chile, and formally synonymize H. canopus and H. polybrachius under H. helianthus. Our results indicate that a single species spans the Eastern Pacific from Ecuador and Peru to central-southern Chile, including offshore islands, underscoring the value of integrative taxonomy for robust delimitation and accurate biodiversity assessments in marine invertebrates. Full article

Based on external morphology, genital anatomy, and a fragment of the mitochondrial 16S rRNA gene, we identified two veronicellid slug species from Chiapas, Mexico: Simrothula prismatica (Simroth, 1914) and Diplosolenodes occidentalis (Guilding, 1824), both newly recorded in the country. The available molecular data supported the identification of D. occidentalis, a species with a documented invasive history in various tropical and subtropical regions worldwide. Although no sequences were available for S. prismatica, the genital anatomy of the specimens was consistent with the original species description. These findings underscore the need for more comprehensive molecular reference databases and continued biomonitoring of veronicellid slugs in Mexico, given their potential ecological and agricultural impacts. These new records increase the known diversity of the group to five species in the country. Full article

A remarkable new pholcid spider species is described from the Democratic Republic of the Congo: Smeringopina polychila sp. nov. The male is distinguished by a unique and previously undocumented structure, here termed the “parachila”, which has not been observed in any other spider to date. The description is complemented by high-quality illustrations, including detailed drawings, photographs, micro-CT scans, and 3D reconstructions of the genitalia and the newly discovered male structure. Remarkable intraspecific variations, both somatic and genitalic, in males are also highlighted and discussed. A phylogenetic analysis based on the cytochrome c oxidase subunit I, 16S ribosomal RNA and histone H3 gene fragments is presented to tentatively place the new species into an existing phylogenetic framework. The results of the molecular analyses confirm that the new species belongs to the subfamily Smeringopinae and is nested within the genus Smeringopina Kraus, 1957. Full article

A new species of Choreutidae, Tebenna acanthophallus sp. nov., from the Huasco Province, Chile, is described. Diagnostic characters, photographs of adults and illustrations of wing venation and genital structures are provided. The new species is supported by morphological and molecular analyses. This finding provides evidence that the family Choreutidae has species native to Chile, and its presence is not the result of introductions from other countries. Full article

The Neotropical region is recognized as the center of diversification of Phalangopsidae. The true extent of this diversity, however, remains understudied, reinforcing the need for further taxonomic investigations. In this study, we describe Igatuia cavernicola gen. et sp. nov., a new genus and species from caves in Igatu village, Chapada Diamantina, central Bahia state, Brazil. The genus is distinguished by unique morphological traits, including ectophallic apodemes with an expanded apex, bearing a ring of minute pores and an inner canal that opens into the ectophallic arc. This description advances our knowledge of subterranean fauna in the region and contributes to a broader understanding of Phalangopsidae cricket diversity in the Neotropics. We also report new records of Sishiniheia, including the first occurrence of the genus in a cave. Full article

The recent update to the list of European herpetofauna species, published in 2020, includes 206 non-avian reptile species. The steppe ribbon racer, Psammophis lineolatus, is a snake species widely distributed across the deserts and semi-deserts of Central Asia and neighboring regions. Previously unrecorded in Europe, two specimens were discovered west of the Ural River during surveys in western Kazakhstan’s northeastern Caspian region. This is the first record of the species in Europe and marks its most northwestern distribution. DNA barcoding analysis revealed substantial mitochondrial diversity in the region, with European specimens having distinct haplotypes (0.73% p-distance), indicating colonization by two different phylogenetic lineages. This discovery highlights the need for further research on the P. lineolatus intraspecific diversity, phylogeography, and taxonomy. Full article

One new species of Laboulbeniaceae, Peyritschiella styngeti, is described and illustrated. It is characterized by appendages with a black constriction at the base, perithecia with four papillae on the apical zone, cruciform bilateral symmetry, and an extremely melanized receptacle. This species was observed on the stylus of the staphylinid Styngetus deyrollei, which is distributed in tropical montane cloud forests in Mexico. Currently, the Laboulbeniales mycobiota in Mexico comprises 82 species, with 11 described growing on species of the Staphylinidae family. Additionally, a compilation of the Laboulbeniales species reported for Mexico and for Staphylinidae species is presented. Full article

Heptophylla gongshana Bezděk & Král, n. sp. from Yunnan, China, is described. The new species, conspicuous in the genus Heptophylla Motschulsky, 1858, by its black body and octomerous antennal club in males, is compared with similar congeners. An iconography including the male genitalia of the new species and the type material of the Heptophyllini taxa described by You-Wei Zhang and found in the Institute of Zoology, the Chinese Academy of Sciences, Beijing, China, is provided. An updated checklist of Heptophyllini (Scarabaeidae: Melolonthinae) is presented, and the validity of the tribe is discussed. Full article

The Order Polycladida comprises a diverse yet understudied group of free-living flatworms, traditionally divided into Cotylea and Acotylea based on the presence or absence of a ventral adhesive organ known as a cotyl. Species identification, particularly within Acotylea, is often challenging due to the need for histological examination of reproductive structures and the scarcity of molecular data. The Tropical Western Atlantic, especially the Caribbean Sea, hosts high polyclad diversity but remains poorly surveyed. This study updates the checklist of Acotylea from the Colombian Caribbean, combining new collections from Santa Marta with the literature records. Field work yielded 22 acotylean species from 14 genera and 10 families, with DNA sequences (28S rDNA and/or COI mtDNA) obtained for 20 species. 11 species are new records for Colombia, and five for the Caribbean Sea: Latocestus brasiliensis Hyman, 1953, Notocomplana martae (Marcus, 1948), Interplana evelinae (Marcus, 1952), Triadomma curvum Marcus, 1949, and Adenoplana evelinae Marcus, 1950. In total, 29 species are now documented from the region. We provide photographs of live specimens, whole mounts, and histological sections; DNA barcodes for most species; and the first dichotomous key for Colombian Caribbean acotyleans, based primarily on external traits, providing a practical tool to support further taxonomic, ecological, and biodiversity research. Full article

Mascagnia (Malpighiaceae) is the lianescent genus with the most convoluted taxonomic history and polyphyly of Malpighiaceae, formerly comprising eight unrelated accepted genera and over 300 species. This genus currently encompasses 48 accepted Neotropical species, of which 20 are reported for Brazil in the taxonomic treatment presented herein. This synopsis was based on the morphological study of specimens deposited in over 80 herbaria using a stereomicroscope, the specialized literature, and consulting type specimens for all accepted species. A total of 20 species of Mascagnia are found in all biomes of Brazil. A taxonomic synopsis is presented for these species, including an identification key, notes on distribution, conservation and taxonomy, and photographic plates for 12 species. Two main morphological groups were identified based on the inflorescence architecture and petal color, and four species were identified as under a conservation threat. Full article

Tetrigidae is a caeliferan family of Orthoptera constituting a diverse and relatively ancient lineage of small Orthopterans, which has its greatest diversity in tropical and subtropical areas. However, to date, few studies have been conducted on the identification and description of Tetrigidae species in Ethiopia, and even fewer molecular data are available. Hence, we performed the first species delimitation study via DNA barcoding of species belonging to the genera Paratettix, Leptacrydium, Dasyleurotettix, and Morphopoides from Ethiopia. We provide 35 new sequences of the COI gene belonging to six species of these genera. We show that Ethiopian Tetrigidae can be successfully delineated using DNA barcodes, even in cryptic genera such as Paratettix: species delimitation on the basis of this gene was strongly congruent with the phylogenetic tree and morphological assignments. We report three species: Dasyleurotettix infaustus (Walker, 1871), Morphopoides tessmanni (Günther, 1939), and M. folipes (Hancock, 1908) from Ethiopia for the first time. In addition, we describe three new species, which were confirmed with morphological, phylogenetic, and species delimitation methods: Paratettix tanai sp. nov., Paratettix geminus sp. nov., and Leptacrydium naqamteensis sp. nov. Further, we studied Paratettix macrostenus, which is considered a new synonym of P. subpustulatus. Future integrative taxonomic studies, including more material from diverse regions, additional genetic loci and more comprehensive taxon sampling, need to be performed to understand the diversity of Tetrigidae across Africa. Full article

In specific altitude ranges, biotic and abiotic factors can impact vector mosquitoes’ adaptation capacity, affecting their population differentiation. This study analyses if there exist morphological and genetic differences in four Anopheles (Kerteszia) populations in specific altitude ranges from the Colombian pacific coast to the premontane humid forests in Valle del Cauca, Colombia. Likewise, it is compared if the vector mosquito groups analyzed were genetically similar to the ones available in the region. Traditional and geometric morphometric analysis and the molecular marker CO-I were used. The research found that vector mosquitoes’ littoral populations differentiated morphologically according to their cross veins wing shapes compared to the other three groups in higher altitudes. Their genetic distances fluctuate between 4.95% and 6.84%, indicating that vector mosquitoes’ littoral populations belong to Anopheles neivai s.s. while the ones of higher altitudes are related to An. neivai 8—a lineage previously proposed based solely on molecular data. The study concludes that vector mosquitoes at the pacific Colombian coast from the littoral area in lower altitudes maintain a vast genetic variability with uniform populations; however, in higher altitudes, vector mosquitoes acquire molecular and morphological differences that may include the settlement of other lineages. Full article

Tabanid species of the Andean genus Agelanius Rondani are revised herein based on an examination of the external morphology of the type material of ten species and specimens from Argentina and Chile. A new species, A. augustus sp. nov., is described, and a new key to the known species is provided. Diagnoses, detailed distributional data for the species of Agelanius, and photographs are included to facilitate species identification. Full article

In this paper, Nanocnide simingshanensis is described as a new species based on morphological and molecular analyses, and its taxonomic relationships are discussed. The new species is currently known only from the Siming Mountain region of Yuyao County and the Yaolin National Forest Park of Tonglu County, both in Zhejiang Province, eastern China, where it grows in shrubs at an elevation of about 650 m under deciduous broad-leaved forests and at a limestone cave entrance. Morphological analysis strongly supports that N. simingshanensis should be classified into the genus Nanocnide. This species is distinguished from the related species N. pilosa and N. lobata by having long straight hirsute hairs perpendicular to the stem, petioles and peduncles, longer petioles, larger leaf blades, and female inflorescences developing on branchlets. It differs from N. zhejiangensis and N. japonica by having glomerulate male inflorescences shorter than leaves (vs. cymose inflorescences longer than leaves). Nuclear ribosomal DNA internal transcribed spacer (ITS) phylogenetic analysis demonstrates that N. pilosa and N. lobata are the closest extant relatives to the new species. Full article

The genera: Lerniana Delicado et Hauffe, 2022, Trichonia Schütt, 1980, and two clades (“Radomaniola” elongata Radoman, 1973, and an unnamed clade referred to as “Radomaniola” sp. 1, sp. 2) whose assignment to any genus remains unknown, form sister group with the genus Radomaniola Szarowska, 2007 (Hydrobiidae W. Stimpson, 1865, subfamily Horatiinae D. W. Taylor, 1966). The paper deals with all these clades sister to Radomaniola. Cytochrome c oxidase subunit I (COI) sequences have been used to infer phylogenetic relationships between the snails collected at 15 localities in southern Greece and one in Montenegro. Thirty-two haplotypes represent eight Molecular Taxonomical Units (mOTUs) of the species level, four of them within the genus Lerniana: L. seminula (Frauenfeld, 1863), L. tritonum (Bourguignat, 1852), and two other of these four species are both described as new. First of them has been found at seven localities in Peloponnese, Attica and southern Thessaly, the second only at one locality, sympatrically with the former species. “Radomaniola” elongata does not belong to Radomaniola, and its relationships remain unknown, similarly as in other unnamed clade, whose genus-level assignment cannot currently be resolved. The shells, protoconchs, radulae, female reproductive organs and penes are presented, also for Trichonia trichonica Radoman, 1973, for which the genus assignment remains undecided based on our molecular results. The study clearly illustrates how fragmentary is our knowledge is on the real biodiversity of the minute truncatelloid gastropods, whose morphology—simple and variable—makes species distinction hardly possible. Informed decisions on species and habitat protection should consider the above. Full article

Despite being the subgenus with the highest number of species within Chimarra Stephens, 1829 in Brazil, information about Chimarra (Curgia) Walker, 1980 is scarce in the Brazilian semi-arid region. Beyond the discussion about the quantity of species reported for this region, there is also a temporal gap concerning original descriptions of this subgenus in Brazil. Thus, 15 years after the last description of C. (Curgia) in Brazil, we diagnosed, described, and illustrated two new species based on adult males collected in the Caatinga and Cerrado biomes in the state of Piauí, viz., Chimarra (Curgia) opala sp. nov. and Chimarra (Curgia) prata sp. nov. They can be recognized mainly by the morphology of tergum X, preanal appendage, and phallotheca spines. Moreover, they do not conform to the characteristics of any species group traditionally known in the genus. While sharing similarities with the species compared in this study, these comparisons are limited to isolated characters and do not encompass all the features representing the groups of their respective species. Full article