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Review

Palms (Arecaceae) and Meligethinae (Coleoptera, Nitidulidae): A Long Evolutionary Journey

by
Meike Liu
1,
Jinting Che
2,
Simone Sabatelli
3,4,*,
Pietro Gardini
3,4,
Simone Fattorini
5,
Andrzej Lasoń
6,
Josef Jelínek
7 and
Paolo Audisio
3,4,*
1
College of Agriculture, Yangtze University, Jingzhou 434025, China
2
MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River (Co-Construction by Ministry and Province), College of Agriculture, Yangtze University, Jingzhou 434025, China
3
Department of Biology and Biotechnologies “Charles Darwin”, Sapienza Rome University, 00185 Rome, Italy
4
National Biodiversity Future Center (NBFC), Piazza Marina 61, 90133 Palermo, Italy
5
Department of Life, Health and Environmental Sciences, University of L’Aquila, Via Vetoio, 67100 L’Aquila, Italy
6
Independent Researcher, ul. Wiejska 4B/85, 15-352 Białystok, Poland
7
Department of Entomology, National Museum, Cirkusová 1740, 9-Horní Počernice, CZ-193 00 Praha, Czech Republic
*
Authors to whom correspondence should be addressed.
Plants 2025, 14(16), 2487; https://doi.org/10.3390/plants14162487
Submission received: 9 July 2025 / Revised: 2 August 2025 / Accepted: 5 August 2025 / Published: 11 August 2025
(This article belongs to the Special Issue Interaction Between Flowers and Pollinators)
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Abstract

Arecaceae (palms) constitute a highly diversified family of monocots, distributed especially in tropical and subtropical areas, including approximately 2600 species and 180 genera. Palms originated by the end of the Early Cretaceous, with most genus-level cladogenetic events occurring from the Eocene and Oligocene onward. Meligethinae (pollen beetles) are a large subfamily of Nitidulidae (Coleoptera), including just under 700 described species, and some 50 genera. Meligethinae are widespread in the Palearctic, Afrotropical, and Oriental Regions. All meligethine species are associated with flowers or inflorescences of several plant families, both dicots (the great majority) and monocots (around 7%); approximately 80% of known species are thought to be monophagous or strictly oligophagous at the larval stage. The origin of Meligethinae is debated, although combined paleontological, paleogeographical, and molecular evidence suggests placing it somewhere in the Paleotropics around the Eocene–Oligocene boundary, ca. 35–40 Mya. This article reviews the insect–host plant relationships of all known genera and species of Meligethinae associated with Arecaceae, currently including some 40 species and just under ten genera (including a possibly new African one). The role of adults as effective and important pollinators of their host palms (also in terms of provided ecosystem services) has been demonstrated in some common palm species. All Meligethinae living on palms show rather close phylogenetic relationships with one another and with the mainly Eastern Palearctic genus Meligethes Stephens, 1830 and related genera (associated with dicots of the families Rosaceae, Brassicaceae, or Cleomaceae). Molecular data suggests that the palm-associated Paleotropical genus Meligethinus Grouvelle, 1906 constitutes the sister-group of Meligethes and allied genera. Some hypotheses are presented on the evolution of Meligethinae associated with palms and their probably rather recent (early Miocene–Pleistocene) radiation on their host plants. Meligethinae likely radiated on palms long after the diversification of their hosts, and their recent evolution was driven by repeated radiation on pre-existing and diverse palm taxa, rather than ancient host associations and coevolution. Finally, this article also briefly summarized the relationships that other unrelated groups of Nitidulidae have established with palms around the world.

1. Introduction

Palms (family Arecaceae) represent a large and highly diversified group of monocotyledonous plants, distributed especially in tropical and subtropical areas, counting worldwide approximately 2600 species and 180 genera (Figure 1) [1,2,3,4,5,6,7]. Members of this clade are widely known for their freeze intolerance (although this varies greatly across different genera and species, organs, and life stages), being able to survive only in areas with coldest month mean temperatures, usually >3 °C, and minimum mean annual temperature of ca. 10 °C [8,9]. Palms likely originated by the end of the Early Cretaceous, around 100 Mya, with most genus-level cladogenetic events occurring from the Middle Eocene (and even more from the late Oligocene) onward [10,11].
Among the diverse floral visitors and potential pollinators of palms are various beetle clades, including the Meligethinae, a subfamily of Nitidulidae (Coleoptera) commonly referred to as pollen beetles (Figure 2, Figure 3, Figure 4 and Figure 5). Meligethinae include just under 700 described species and are present in almost all the world—except for the Neotropical Region and Antarctica—being particularly numerous in the Palearctic, Afrotropical, and Oriental Regions [12,13,14]. All known meligethine species are closely associated during their larval development with flowers or inflorescences of a wide variety of different plant families, both dicots (the great majority) and monocots (ca. 7% of known species). Despite the ecological and evolutionary interest of this plant–insect association, the relationships between Meligethinae and palms (Figure 6) remain poorly studied and likely underestimated, partly due to limited sampling, the sometimes unpredictable palm flowering phenology, and the meligethine taxonomic complexity.
This review aims to synthesize current knowledge on the ecological and evolutionary relationships between meligethine beetles and palms, with an emphasis on host plant use, pollination roles, biogeographical patterns, and diversification mechanisms. We explore how this plant–insect interaction evolved, whether coevolution played a significant role, and to what extent palms have served as drivers of diversification for the Meligethinae. Finally, we highlight existing knowledge gaps and outline future research directions necessary to better understand this fascinating yet overlooked system.

2. Origin of the Meligethinae

The origin of the Meligethinae is still debated, although paleogeographical, paleontological, and molecular clock evidence suggests a Paleotropical origin around the Eocene–Oligocene boundary, approximately 40 Mya [12]. In earlier geological periods, their ecological role of anthophagous beetles was likely occupied by several now-extinct and distantly related clades of other Nitiduloidea lineages, such as ancient genera of Kateretidae, ancient Nitidulidae Epuraeinae, and Nitidulidae Apophisandrinae. The latter may have acted as pollinators for different plant families within the Nymphaeales clade, and possibly even for some Gymospermae and Cycadales [19,20,21].
The earliest fossil genus currently assigned to the Meligethinae is Melipriopsis Kirejtshuk, 2011, which includes two related species found in Eocene Baltic amber, dating to approximately 48–34 Mya [22,23,24,25]. However, this genus cannot be confidently placed within the true Meligethinae with certainty, due to several anomalous morphological traits, including the distinctly bordered posterior base of pronotum, the rather acutely sinuated axillary line on the metaventrite (consequently, with a markedly reduced “metasternal axillary space”), and the presence of long cilia along the outer edges of both the pronotum and elytra. All these features are, in fact, inconsistent with the current delimitation of modern Meligethinae [13,14,26]. Similar long cilia are found only in the southern African, sub-eremic and monotypic genus Sebastiangethes Audisio & Kirk-Spriggs, 2008, and, even there, they occur only along the outer lateral edges of the elytra. Thus, the oldest probably true fossil meligethine appears to be “Meligethes” detractus B. Förster, 1891 from the Saxonian Early Oligocene, dated approximately to 30–35 Mya [23,24,25,26,27,28]. A questionable fossil member of the genus Pria Stephens, 1830 from Baltic amber (ca 40 Mya), might also represent an early meligethine lineage [29]. All these approximate dates appear to be compatible with available molecular evidence, which estimates the origin of the so-called and clearly quite recent “Meligethes complex of genera” at around 15 Mya, while the origin of some of the probably most archaic genera of Meligethinae (such as Acanthogethes Reitter, 1871, Lariopsis Kirejtshuk, 1989, Lamiogethes Audisio & Cline, 2009, and Afrogethes Audisio & Cline, 2009) could be dated to around 25–30 Mya [12,13,14,30] (Audisio et al. unpublished data; Figure 7 and Figure 8). Unfortunately, no additional paleogeographical data is available to support a more reliable and accurate estimate of the origin of Meligethinae, which most likely originated somewhere in the Afrotropical Region and subsequently dispersed into Europe and Asia.
On the other hand, there is still an almost complete lack of molecular data to accurately estimate the origin of the subfamily. Based on available evidence, the Meligethinae appear to be the sister-group of the “Nitidulinae 2” group of Lee et al. [31], which corresponds to the so-called “Soronia complex of genera” (known as fossil at least from Paleogene), making the Nitidulinae a paraphyletic group [20,31,32]. In fact, the “subfamily” Nitidulinae, as currently delimited, is a heterogeneous and paraphyletic assemblage that will likely require reclassification in the near future into a small number of credibly monophyletic subfamilies [31,33], one of which would obviously be represented by the Meligethinae.
The combined estimates of the origins of palms and the Meligethinae discussed above suggest that the latter emerged during a geological period in which a large part of the Arecaceae had already diversified. This timing would have allowed the Meligethinae to exploit a pre-existing, broad, and diversified ecological and phylogenetic space, especially during the last 20 My, through a model of sequential evolution [34,35,36]. However, this observation does not preclude the possibility of limited and recent instances of true coevolution [37] between the Meligethinae and the Arecaceae, particularly within the last 10–15 My. This mixed evolutionary pattern is consistent with recent molecular evidence from the genera/subgenera Meligethes Stephens, 1830, and Odonthogethes Reitter, 1871, in relation to the evolutionary history of their Rosaceae host plants (especially of the speciose genera Rosa L. and Rubus L.) in the Eastern Palearctic [14] (Liu et al. unpublished data). In these cases, as well, the main diversification and evolution of the host plants clearly preceded that of their associated pollen beetles, which likely underwent more recent species-level diversification associated with both Rosa and Rubus evolution in montane areas of China, Nepal, and surrounding areas, during the last few million years [14].

3. The State of the Art of Meligethinae Diversification and Taxonomy

Until a few years ago, the vast majority of known Meligethinae species (>500 out of <700) were attributed to the vast genus Meligethes. However, both morphological and molecular evidence revealed that the Meligethes represented a heterogeneous and clearly polyphyletic “wastebasket taxon” [12,13,26,38,39]. In response, Audisio et al. [12] tentatively revised and split this taxon into approximately twenty distinct genera, most of which roughly corresponded to the former subgenera or major species-groups previously recognized within the Meligethes. Within each of these lineages, most species tend to share the same larval host plant family.
A recent paper [40] proposed a number of new synonymies across various genera within the subfamily Meligethinae, based on very limited data and a simplistic approach. The authors of this article also advocated for the reintroduction of an earlier classification system for the subfamily—one that has since been proven to be untenable, especially in the light of molecular evidence [13,14,41,42]. Given these shortcomings, the taxonomic conclusions presented in that article are not considered further here.
Following the taxonomic and phylogenetic review by Audisio et al. [12]—which will still require additional studies, re-analysis, and refinements using more advanced (e.g., metagenomic) approaches—the nominotypical “subgenus” Meligethes (together with the closely related subgenus or genus Odonthogethes) is currently understood to include about seventy species from the Palearctic and Oriental regions, all closely associated, during their larval development, with the flowers of Rosaceae [13,14,41,42]. As demonstrated in a series of recent papers [12,13,14,39,43,44,45,46], Meligethes, Odonthogethes, and Brassicogethes Audisio & Cline, 2009, form a well-defined and monophyletic clade (Figure 7 and Figure 8), mainly distributed in the Palearctic region. This clade includes just under 110 species, all of which are associated with particular host plant families, Meligethes and Odonthogethes with Rosaceae (within the clade Eurosids I, order Rosales) and Brassicogethes with Brassicaceae and Cleomaceae (within the clade Eurosids II, order Brassicales).
Sister to this small but speciose clade (then, only including the three genera Meligethes, Odonthogethes, and Brassicogethes, each of them comprising several dozen species) is the palm-associated genus Meligethinus Grouvelle, 1906 [12,13,14,43] (Liu et al. unpublished metagenomic data). This genus is also related to a group of other small- to mid-sized meligethine genera known from the Palearctic, Oriental, and Afrotropical–Malagasy regions, including, among others, Kabakovia Kirejtshuk, 1979, Cryptarchopria Jelínek, 1975, Horakia Jelínek, 2000, Pria Stephens, 1830, Tarchonanthopria Audisio & Cline, 2014, and the tentatively introduced Microporum Waterhouse, 1859 group of genera [12,13,14,15,40,43,47,48,49,50,51,52,53,54]. It is likely that an ancient common ancestor of these genera shifted from dicots to a distantly related monocot plant family. This host shift may have triggered a rapid adaptive radiation into a newly available ecological and phylogenetic space (i.e., the highly diverse monocot plants), following evolutionary trajectories similar to those discussed elsewhere [55,56,57,58]. Among these probably more recently originated genera, two small lineages show evident specializations: the Meligethinus group of genera on male inflorescences of Arecaceae (palms) (Figure 6a,b) and a few genera of the Microporum group on inflorescences of Pandanaceae (screw pines) [12,13,15,17,47,48,49,50,53,54,59]. In particular, several mostly Oriental and Afrotropical species within the Meligethinus complex of genera (Table 1) are known to be associated with palms during both larval and adult stages [12,13,40,54,59,60]. However, some recent reviews [6,61] appear to have overlooked the important role of the Meligethinae in palm pollination and conservation.

4. The Dicot–Monocot “Host Jump”

As noted elsewhere [67,68,69,70], the number of phytophagous (and/or anthophagous) insect species tends to be positively correlated with the diversity of their host plant taxa. This suggests that when a group of insects undergoes a “host jump” to another new, phylogenetically distant group of plants, they may gain an evolutionary advantage over competitors. If the new host plant group represents an ecologically and trophically open niche—providing abundant, annually stable, and phylogenetically diversified resources—this can facilitate a rapid radiation of the insects within the newly colonized plant lineage [71,72]. Such a model may explain the early evolution of Meligethinae, which first made a “host jump” from dicots to monocots, quickly colonizing an already well-diversified group, the palms. This evolutionary trajectory seems to be recurrent in phytophagous insects, since similar evolutionary phenomena involving recurrent and independent host jumps from dicots to monocots have been documented, e.g., in Chrysomelidae [73]. Recent research indicates that strict cospeciation events are relatively rare (ca. 7%) among phytophagous insects [56]. Instead, cases of “sequential” evolution and adaptive radiation following host shifts to novel, distantly related and already highly diversified host groups are more common [73].
In this context, it has recently been emphasized [67,74,75,76] that similar evolutionary patterns in insect–plant interactions are consistent with the earlier observations of Janzen [75,76] on the theoretical parallel between the evolution of phytophagous insects and principles of insular biogeography. According to this view, when a phytophagous insect clade colonizes a new, phylogenetically distant but highly diversified “plant archipelago”, a rapid adaptive radiation within that host group is likely to occur.

5. The Evolution of the Meligethinae on Monocots and Palms

As regards the identity of the ancestral lineages from which the dicot-to-monocot ecological shift—or, more precisely, the “host jump” [56,77]—occurred among the Meligethinae, probably around 20 Mya, the best candidates are almost certainly to be found among the present-day members of the “Anthystrix complex of genera”. This group [also] includes the Oriental Cyclogethes Kirejtshuk, 1979, and the related Afrotropical genus Chromogethes Kirejtshuk, 1989, both associated, in the larval stage, with inflorescences of Asteraceae [12,13,26,38,41,42,78]. Species within the “Anthystrix complex of genera” exhibit clear molecular and morphological evidence of phylogenetic relatedness to most of the monocot-associated Meligethinae ([13,39,41,60]; Figure 7), supporting their likely ancestral role in the host shift event. It is also worth noting that a few other meligethine lineages—unrelated to each other—have independently made similar, though more limited, “host jumps” from dicots to monocots. Notable examples include Restiopria Audisio, 2011 (a genus comprising a single known species from the southern African Cape Province, associated with prostrate Restionaceae), and Afrogethes heteropus (Gerstaecker, 1871), a phylogenetically isolated Afrotropical species found in Central and Western Africa and associated with Poaceae [13,17,79,80].
Based on clear morphological evidence, the genus Pria appears not distantly related to all meligethine genera associated with palms (Table 1; Figure 7) or with other monocots (such as the genus Microporum, found in the western Indian Ocean islands and associated with the inflorescences of Pandanaceae). Pria, which includes around 80 species primarily across the Paleotropics [49], probably shares a far common ancestor with Meligethinus and its allied genera, as well as with the above listed members of the “Anthystrix complex of genera” (Figure 7) [12,13,49]. Species of Pria—a genus distinguished by the absence of the pair of large semicircular impressions on the last abdominal ventrite, a feature present in nearly all other Meligethinae, except Palmopria and allied Afrotropical genera, and Oriental Horakia + Cryptarchopria—have undergone multiple host shifts into dicot lineages. These shifts have led to radiation into several plant families, particularly Solanaceae, Ericaceae, Mesembryanthemaceae, Asteraceae, and possibly also Buddlejaceae [12,13,49], (Audisio et al. unpublished data). Afrogethes, Lamiogethes, Lariopsis, and also some basal members of the “Anthystrix complex of genera” were already well differentiated by approximately 25–30 Mya [30]. Possibly around 20 Mya, a lineage phylogenetically related to Meligethinus and its relatives likely shifted to monocot hosts, including Arecaceae and Pandanaceae, probably within the Paleotropical region. It is particularly noteworthy that members of the Meligethes complex of genera—the recognized sister group of Meligethinus—appear to have undergone a retrograde “host-jump” back from monocots to dicots (Rosaceae and Brassicaceae) in the Eastern Palearctic [13,14]. This interpretation is consistent with the combined molecular, morphological, and biogeographical evidence currently available (Figure 7 and Figure 8).
It is also important to note that our knowledge of palms-associated Meligethinae is probably far from complete, due to the rarity of certain palm species and the limited opportunities for entomologists to encounter them in bloom—an essential condition for collecting associated beetles. As a result, new palm-associated taxa continue to be occasionally discovered in tropical areas ([18,40,62]; Table 1). An emblematic example of this knowledge gap concerns the iconic and rare giant palm Raphia australis Oberm. & Strey, commonly known as the Kosi palm or umVuma (in Zulu). This threatened palm occurs in a very limited area between the southern Mozambique and northeastern South Africa [81,82,83,84,85]. Raphia australis is monoecious and monocarpic, producing its massive male and female inflorescences only once in its lifetime. Despite a series of research projects focused on insect biodiversity associated with local palms, our team was unable to locate flowering individuals in southern Mozambique in recent years due to the unpredictability and brevity of their flowering period [18]. Because of the large number of palm species endemic to tropical Africa and to southeastern Asia, from northeastern India to the Philippines and Indonesia, new palm-associated species and genera of Meligethinae are likely to be discovered as more intensive fieldwork and taxonomic studies are undertaken in these areas.
Returning to the key genus Meligethinus—which probably represents the starting point for the adaptive radiation of Meligethinae on palms—all members of this predominantly Paleotropical clade (Table 1) appear to be strictly associated with the male inflorescences (spathes) of palms during their larval development. Adults are also rarely found outside these inflorescences, typically only after the usually brief flowering period of the respective host plants has ended [63]. Meligethinus has been regarded as perhaps the most archaic of all palm-associated Meligethinae [40,53,54] due to several plesiomorphic traits it shares with other Meligethinae, such as members of the previously mentioned Meligethes genus complex. Most species within this clade appear to be strictly monophagous, although a few exhibit oligophagy [12,16,17,18,62,86,87] (Liu & Audisio, unpublished data]. Some species of Meligethinus (e.g., M. pallidulus Erichson, 1845 from the southwestern Mediterranean, M. tschungseni Kirejtshuk, 1987 from China, and some widespread African species) also act as important pollinators of cultivated or ornamental palms, such as Chamaerops humilis L., Trachycarpus fortunei (Hook.) H. Wendl., Elaeis guineensis Jacq. and Phoenix reclinata Jacq. (Table 1; Figure 6a,b) [17,18,62,87,88]. Some meligethine genera and species certainly provide notable ecosystem services, particularly in agricultural contexts. In natural ecosystems, most Meligethinus species play a major role in the pollination of native palms, including species of conservation concern, from the southwestern Mediterranean (Figure 6a) through the Near East, as well as in the Oriental and Afrotropical regions [16,17,18,54,62,88,89,90,91] (Audisio et al. unpublished data). Therefore, it would be particularly important to determine whether an as yet undiscovered species of Meligethinus (or of a related genus) might be involved in the pollination of the aforementioned rare and threatened southern African Kosi palm (Raphia australis). Such a discovery could have significant implications for the species’ survival and inform future conservation strategies.
Finally, when examining the relationships between the relatively large genus Meligethinus and its palm host plants, it is noteworthy that these interactions are consistent with recent findings from other host–parasite systems, in which coevolution between hosts and parasites is rarely a major driver of speciation [37], except in cases of obligate pollination mutualisms, where close co-adaptation may be involved [57,92,93,94]. In this context, it is interesting to note that some palm species (e.g., Elaeis guineensis and Phoenix reclinata in tropical Africa: Table 1) [18,62] may simultaneously host larvae and adults of up to five species of Meligethinus, even in the same locality and on the same individual palm; these pollen beetle species are often not strictly related phylogenetically, as on the contrary one might expect in the case of sympatric speciation. This evidence suggests that the evolution of Meligethinae on palms has been shaped more by a combination of independent allopatric speciation events, subsequent geographical overlap through range expansion, and repeated host shifts (or “host-switching” [95]) rather than by coevolutionary processes. This hypothesis seems to be strongly strengthened by repeated observations that demonstrate how local multi-specific associations of Meligethinus on individuals of the same palm species are highly dynamic, varying from location to location throughout tropical Africa; this circumstance well supports the assumption that (at least) in tropical and equatorial Africa, where the presence of many palm species in the same area is very common, each Meligethinus species has a notable propensity to easily colonize new palm hosts, even when the latter are not at all phylogenetically related to one another. In fact, the few apparently strictly monophagous species of this genus are only those that live in areas marginal to the main palm range (Figure 1), such as Meligethinus pallidulus in the western Mediterranean coastal maquis, M. gedrosiacus in the Iranian–Arabian deserts, and the common M. tschungseni in central China forests (Table 1), where only a single native palm species (in the latter case Trachycarpus fortunei (Hook.) H. Wendl.) is present. This interpretation is also consistent with the “oscillation hypothesis” of host plant range evolution and speciation in phytophagous insects, which emphasizes dynamic shifts between host specialization and generalization over evolutionary time and space [96,97,98].

6. Palms and Other Pollen-Eaters, Pollinators, or Inflorescence-Frequenters Nitidulid Beetles

For the sake of completeness, it is also important to note that in Central and Southern America, where the Meligethinae are absent, palms host a large variety of other anthophagous and pollinating Nitidulidae, mostly represented by the ecologically and geographically vicariant tribe (or subfamily) Mystropini [62,99,100,101,102,103,104,105,106]. When considered as a tribe, the Neotropical Mystropini (which share several markedly convergent external traits with Old World Meligethinae, especially with those analogously developing on palm inflorescences), are currently classified within the subfamily Nitidulinae, a paraphyletic group, as discussed above [31,33].
Finally, other groups of nitidulids have also independently established specialized relationships with male inflorescences of palms. For example, members of the Epuraeinae, such as all representatives of the Afrotropical subgenus Apria Grouvelle, 1919 (within the large and heterogeneous genus Epuraea Erichson, 1843, strongly needing a complete revision), are known to frequent palm inflorescences [62,107]. Similarly, other Epuraeinae of the same genus have been reported as regular pollinators of the Oriental palm Nypa fruticans Wurmb. [108,109,110]. A particularly isolated lineage, the subfamily Cillaeinae Kirejtshuk & Audisio, 1986, includes some tropical members typically associated as both larvae and adults with senescent palm stalks and inflorescence sheaths, where they primarily feed on different genera and species of filamentous fungi, being rarely found on fresh palm inflorescences [17,89,111,112]. Interestingly, recent studies on the insect pollinators of the Indonesian and Philippine palm Nypa fruticans Wurmb. report, in addition to Epuraea spp., some other unidentified Nitidulidae, including members of the above cited subfamily Cillaeinae (likely belonging to the genus Brachypeplus Erichson, 1842) [108,109,110].

7. Conclusions

Table 1 summarizes the most updated information on the ecological (demonstrated or inferred) relationships between Meligethinae and palms, and it includes several unpublished data on both described and undescribed pollen beetle species. As discussed throughout this review, the probably monophyletic meligethine group first associated with Arecaceae likely originated from a sudden “host jump” from dicots to monocots approximately 20 Mya. This event subsequently led to the emergence and diversification of the entire clade of the Palearctic Meligethes-complex of genera, later followed by a likely retrograde host shift back to dicotyledons. Notably, this latter shift involved plant families (Rosaceae, Brassicaceae, and Cleomaceae) that had not previously, or elsewhere, been colonized by the Meligethinae. In the meantime, the aforementioned “host jump” may have enabled the Meligethinae to exploit a newly available, ecologically open plant lineage—the Arecaceae—which was largely free of both natural enemies and competitors, thereby triggering a rapid adaptive radiation of this small pollen beetle lineage. As a result, nearly forty species and around ten genera are now known to be associated with a wide variety of phylogenetically diverse and pre-existing palm taxa. This hypothesis is consistent with recent studies showing that coevolution between hosts and their parasites is rarely a major driver of speciation [37,106,113,114,115]. Notable exceptions can be represented by cases of obligate pollination mutualism with highly specialized partners [92,93,94,116]. In line with this view, we have highlighted how certain palm species (e.g., Elaeis guineensis and Phoenix reclinata in tropical Africa: Table 1) [18,62] can host both larvae and adults of up to five species of Meligethinus, even on the same individual palm (Figure 6b). These co-occurring beetle species are often not closely related, further suggesting a lack of strict host-specific coevolution [55,117]. These observations support a model in which the evolution of Meligethinae on palms has likely been shaped by a combination of independent allopatric speciation events, secondary sympatry through range expansion, and repeated host shifts among (related and unrelated) already well-differentiated palm species. Similar evolutionary scenarios were recently observed in other unrelated pollinator beetle lineages, such as several members of the weevil tribe Derelomini [106,113,114,115]. Members of this lineage have been listed as a typical example of “brood-site pollination mutualism”—or nursery pollination, BSPM—a concept recently discussed by Haran et al. [106] to indicate an insect–host plant system where immature stages of a pollinator develop within tissues (either flowers, ovules, or pollen) of a plant as a reward for its pollination (made by the flying adult individuals of the involved species); this same concept can easily be applied to all palm-associated Meligethinae.
We also emphasize that the actual diversity of the Meligethinae associated with palms is likely severely underestimated. This underestimation is primarily due to a lack of targeted field research, the rarity of many palm species, and their often brief and unpredictable flowering periods, which hinder regular insect sampling.
Finally, we highlight the ecological and economic importance of certain meligethine species as pollinators—not only for agricultural and ornamental palms but also for species of high conservation concern. Further studies are clearly needed to assess their pollination efficiency, the degree of specialization (monophagy vs. oligophagy) [118,119,120,121], and their ecological uniqueness in palm pollination systems [122].

Author Contributions

Conceptualization, P.A. and M.L.; methodology, J.C., P.G., S.F. and A.L.; software, M.L., S.S. and P.A.; validation, S.S., J.J. and P.A.; formal analysis, M.L., S.S., and P.A.; investigation, J.C., S.S., P.G. and S.F.; resources, M.L., S.S., A.L. and P.A.; data curation, M.L., S.S. and P.A.; writing—original draft preparation, M.L. and P.A.; writing—review and editing, M.L., P.A., S.F., J.J., A.L. and S.S.; supervision, P.A. and S.S.; funding acquisition, M.L. and P.A. All authors have read and agreed to the published version of the manuscript.

Funding

This research was partly funded by the National Natural Science Foundation of China [grant number 32000321] to M.L. M.L. also thanks the China Scholarship Council for financial support during her stay in Italy (November 2016–November 2017), under the supervision of P.A. Additional funding was provided by the Project “Training in Biodiversity and Biotechnology for sustainable development” (AID 11096) funded by the Italian Agency of Cooperation for Development and by the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.4—Call for tender No. 3138 of 16 December 2021, rectified by Decree No. 3175 of 18 December 2021 of the Italian Ministry of University and Research, funded by the European Union—NextGenerationEU (Project code CN_00000033, Concession Decree No. 1034 of 17 June 2022, adopted by the Italian Ministry of University). Research of J.J. was supported by the Ministry of Culture of the Czech Republic (DRKVO 2024-2028/5.I.a, National Museum, 00023272).

Acknowledgments

The authors are grateful to Mauro M. Colombo, Elisa Taviani, and Piero Cappuccinelli (Dep. of Biomedical Sciences, Univerisity of Sassari, Italy), as well as to the entire staff of the Museu de História Natural of Maputo (Mozambique). Thanks are also given to Tammo Reichgelt (Columbia University, New York, USA) for granting permission to use and integrate Figure 1b of his recent contribution on palm ecology [8], and to our friend Nicolò Falchi (Italy) for his beautiful color painting represented in Figure 4. The authors are also grateful to the following museum curators for enabling P.A. to study important Meligethinae preserved in their institutions: Max Barkley (Natural History Museum, London, UK), Antoine Mantilleri (Muséum National d’Histoire Naturelle, Paris, France), Marc De Meyer (MRAC), Simon Van Noort (Iziko South African Museum, Cape Town, South Africa). The authors are also grateful to G. Powell (Caroline State University, USA) for kindly providing us with a fully annotated tree with individual terminals labeled from Figure 3 of the recent contribution by Powell et al. [72]. Finally, the authors are grateful to three unknown reviewers, who certainly contributed to improving the clarity and quality of the article.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Global distribution of palm species (red points: primary distribution; blue points: secondary distribution, mainly resulting from human-mediated introductions of ornamental or cultivated species) and (green line) known primary and secondary distribution of Meligethinae associated with palms. Redrawn from Reichgelt et al. [8], with permission.
Figure 1. Global distribution of palm species (red points: primary distribution; blue points: secondary distribution, mainly resulting from human-mediated introductions of ornamental or cultivated species) and (green line) known primary and secondary distribution of Meligethinae associated with palms. Redrawn from Reichgelt et al. [8], with permission.
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Figure 2. Habitus of a male specimen of Palmopria elaeidis S. Endrödy-Younga, 1978, from the Democratic Republic of Congo; body length: ca. 3 mm. From Endrödy-Younga [15].
Figure 2. Habitus of a male specimen of Palmopria elaeidis S. Endrödy-Younga, 1978, from the Democratic Republic of Congo; body length: ca. 3 mm. From Endrödy-Younga [15].
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Figure 3. Male specimen of Microporodes dispar (Murray, 1864) from Madagascar; body length: ca. 3 mm. Photo by A. Lasoń.
Figure 3. Male specimen of Microporodes dispar (Murray, 1864) from Madagascar; body length: ca. 3 mm. Photo by A. Lasoń.
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Figure 4. Habitus of a male specimen of Kabakovia sp. cfr. ivoriensis from Uganda (Audisio et al., unpublished); body length: ca. 3.2 mm. Color plate by Nicoló Falchi.
Figure 4. Habitus of a male specimen of Kabakovia sp. cfr. ivoriensis from Uganda (Audisio et al., unpublished); body length: ca. 3.2 mm. Color plate by Nicoló Falchi.
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Figure 5. Habitus of a second instar larva of Meligethinus pallidulus (Erichson, 1845), reared from male inflorescences of the Western Mediterranean dwarf palm Chamaerops humilis L. in Italy. From De Marzo [16].
Figure 5. Habitus of a second instar larva of Meligethinus pallidulus (Erichson, 1845), reared from male inflorescences of the Western Mediterranean dwarf palm Chamaerops humilis L. in Italy. From De Marzo [16].
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Figure 6. Male inflorescences of palms hosting numerous specimens (larvae and adults) of Meligethinus species: (a) male inflorescences of the Mediterranean dwarf palm, Chamaerops humilis L. from Circeo National Park, Italy, hosting hundreds of individuals (larvae and adults) of Meligethinus pallidulus (Erichson, 1845) [17]. Photo by P. Audisio; (b) male inflorescences of Phoenix reclinata Jacq. from Inhaca Island, southern Mozambique, hosting inside hundreds of individuals (larvae and adults) of five different species of African Meligethinus [18]. Photo by S. Sabatelli.
Figure 6. Male inflorescences of palms hosting numerous specimens (larvae and adults) of Meligethinus species: (a) male inflorescences of the Mediterranean dwarf palm, Chamaerops humilis L. from Circeo National Park, Italy, hosting hundreds of individuals (larvae and adults) of Meligethinus pallidulus (Erichson, 1845) [17]. Photo by P. Audisio; (b) male inflorescences of Phoenix reclinata Jacq. from Inhaca Island, southern Mozambique, hosting inside hundreds of individuals (larvae and adults) of five different species of African Meligethinus [18]. Photo by S. Sabatelli.
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Figure 7. Phylogram (obtained using MrBayes) of selected genera within Meligethinae, representing a significant portion of the lineages relevant to our discussion on the origin of palm-associated Meligethinae. Numbers at the nodes represent Bayesian posterior probabilities. The larval host plant family for each analyzed species is indicated. Each species is assigned to one of the following informal clades of genera: [Anthystrix complex of genera + Chromogethes] (red); [Meligethes complex of genera] (green); [Pria complex of genera + Cryptarchopria] (blue). Modified and re-drawn, based on original data and methods, from [13].
Figure 7. Phylogram (obtained using MrBayes) of selected genera within Meligethinae, representing a significant portion of the lineages relevant to our discussion on the origin of palm-associated Meligethinae. Numbers at the nodes represent Bayesian posterior probabilities. The larval host plant family for each analyzed species is indicated. Each species is assigned to one of the following informal clades of genera: [Anthystrix complex of genera + Chromogethes] (red); [Meligethes complex of genera] (green); [Pria complex of genera + Cryptarchopria] (blue). Modified and re-drawn, based on original data and methods, from [13].
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Figure 8. Time-calibrated BEAST phylogeny of representative members of Meligethes s.str. Odonthogethes, Brassicogethes, and Meligethinus, inferred from combined mitochondrial sequences (COI, 16S). Numbers at nodes correspond to estimated age (Mya) obtained with calibration of 0.0126 substitutions/site per My; bars represent highest posterior densities (95%) around mean date estimates. Nodes with black dots were supported with high posterior support (>95). From [14].
Figure 8. Time-calibrated BEAST phylogeny of representative members of Meligethes s.str. Odonthogethes, Brassicogethes, and Meligethinus, inferred from combined mitochondrial sequences (COI, 16S). Numbers at nodes correspond to estimated age (Mya) obtained with calibration of 0.0126 substitutions/site per My; bars represent highest posterior densities (95%) around mean date estimates. Nodes with black dots were supported with high posterior support (>95). From [14].
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Table 1. Genera and species of known or inferred palm-associated Meligethinae, with relevant information on their geographical distribution, habitat, altitude, phenology, and larval host plants. Genera are listed in a tentative phylogenetic order, while species within each genus are arranged alphabetically. Phenological data refers primarily to specimens collected on the inflorescences of host plants in order to reduce the influence of incidental findings outside their actual reproductive period. Several genera are here retained in their original generic rank, disregarding the unjustified and overly simplified synonymies with the genera Microporum C. Waterhouse, 1876 (Lechanteuria), Cornutopria S. Endrödy-Younga, 1978 (Palmopria), or Cryptarchopria Jelínek, 1975 (Horakia, Kabakovia), as proposed by Kirejtshuk and Kirejtshuk [40]. Bionomical, phenological, and distributional data is derived from literature sources [12,13,15,16,17,18,40,50,51,52,53,59,60,62,63,64,65] and is integrated with unpublished data [Audisio et al., unpublished].
Table 1. Genera and species of known or inferred palm-associated Meligethinae, with relevant information on their geographical distribution, habitat, altitude, phenology, and larval host plants. Genera are listed in a tentative phylogenetic order, while species within each genus are arranged alphabetically. Phenological data refers primarily to specimens collected on the inflorescences of host plants in order to reduce the influence of incidental findings outside their actual reproductive period. Several genera are here retained in their original generic rank, disregarding the unjustified and overly simplified synonymies with the genera Microporum C. Waterhouse, 1876 (Lechanteuria), Cornutopria S. Endrödy-Younga, 1978 (Palmopria), or Cryptarchopria Jelínek, 1975 (Horakia, Kabakovia), as proposed by Kirejtshuk and Kirejtshuk [40]. Bionomical, phenological, and distributional data is derived from literature sources [12,13,15,16,17,18,40,50,51,52,53,59,60,62,63,64,65] and is integrated with unpublished data [Audisio et al., unpublished].
Genera and SpeciesDistribution
habitat
(Phenology)
Altitude		Larval Host Plant(s)
(Arecaceae)
Microporodes S. Endrödy-Younga, 1978 Madagascar
tropical forests		Arecaceae
 Microporodes dispar (Murray, 1864) Madagascar
(VII–VIII)
(300–600 m)		Elaeis guineensis Jacq.
Palmopria S. Endrödy-Younga, 1978 Tropical Africa
tropical forests		Elaeis guineensis Jacq.
 Palmopria congolensis (Grouvelle, 1915)Tropical western Africa (from Sierra Leone and Togo to Democratic Republic of Congo and Angola)
(X–V)
(0–1000 m)		Elaeis guineensis Jacq.
 Palmopria elaeidis S. Endrödy-Younga, 1978Tropical western Africa (at least from Togo to Democratic Republic of Congo and Angola)
(X–II)
(0–1600 m)		Elaeis guineensis Jacq.
 Palmopria tomentosa S. Endrödy-Younga, 1978Tropical western Africa (at least from São Tomé to Democratic Republic of Congo and Angola)
(X–II)
(0–1200 m)		Elaeis guineensis Jacq.
Cornutopria S. Endrödy-Younga, 1978 Democratic Republic of Congo
tropical forests		Probably Arecaceae but formally unknown
 Cornutopria basilewskyi S. Endrödy-Younga, 1978As above
(VIII–IX)
(300–500 m)		unknown
Lechanteuria S. Endrödy-Younga, 1978 (1)Tropical western Africa (Guinea to Democratic Republic of Congo)
tropical forests		Probably Arecaceae or Moraceae but unknown with certainty (2)
 Lechanteuria binotata (Lechanteur, 1955)Democratic Republic of Congo
(VIII–IX)
(200–500 m)		Unknown (2)
 Lechanteuria corbisieri (Kirejtshuk, 1980) (1)Democratic Republic of Congo
(VIII–IX)
(200–500 m)		Unknown (2)
 Lechanteuria interrupta (Kirejtshuk, 1980) (1)Democratic Republic of Congo
(IX–X)
(800–1000 m)		Unknown
 Lechanteuria sp. (Audisio et al., unpublished) (3)Guinea
(IX)
(1400 m)		Unknown
Cryptarchopria Jelínek, 1975Oriental Region
tropical forests		Various genera and species of Arecaceae
 Cryptarchopria infima (Grouvelle, 1895)Indonesia (Java, Moluccas Islands)
(X–XI)
(0–500 m)		Areca catechu L.
 Cryptarchopria kabakovi Kirejtshuk, 1979Vietnam
(III–VI)
(0–200 m)		Arenga spp.
 Cryptarchopria ponomarenkoi Kirejtshuk, 1989Vietnam, N Thailand
(V–VI)
(1000–1500 m)		Caryota mitis Lour.
 Cryptarchopria sp. nov. 1 (Jelínek, unpublished) (4)Indonesia, Sangir Island (=Sangihe Island)
(XI)
(200–600 m)		Almost certainly Arecaceae but formally unknown
Horakia Jelínek, 2000 NW Thailand, and border areas between SW China and the
E Arunachal-Pradesh (NE India)
subtropical mountain forests		Arecaceae (maybe all on Caryota spp.)
 Horakia kubani Jelínek, 2000NW Thailand
(V–VI)
(1100–1600 m)		Probably Caryota obtusa Griff. (=C. gigas Hahn ex Hodel)
 Horakia sp. nov. 1 (Liu et al., unpublished) (5)Southern-western China
(Tibet, Medog County)
(VII)
(1400–1500 m)		 Caryota maxima Blume
 Horakia sp. nov. 2 (Lasoń et al., unpublished) (5)Border area between SW China and the E Arunachal-Pradesh (NE India)
(V–VI)
(1500–1800 m)		Unknown, maybe Caryota sp.
Kabakovia Kirejtshuk, 1979 Oriental and Afrotropical Regions
tropical and subtropical forests		Phoenix spp. and other Arecaceae
 Kabakovia ivoriensis (Kirejtshuk & Kirejtshuk, 2012) (6)Ivory Coast
(XI–XII)
(0–200 m)		Probably Borassus akeassii
Bayton, Ouédr. & Guinko
 Kabakovia latipes (Grouvelle, 1908)India, Sri Lanka, Nepal, Vietnam
(III–VI)
(0–1800 m)		Phoenix loureiroi Kunth (=P. humilis and P. hanceana)
 Kabakovia nepalensis (Kirejtshuk & Kirejtshuk, 2012)Nepal
(VIII–IX)
(150–300 m)		Unknown but probably Borassus flabellifer L.
 Kabakovia sp. (6)Uganda
(IV)
(1200 m)		Unknown but probably Borassus aethiopum Mart.
Meligethinus Grouvelle, 1906Oriental, Afrotropical, and southern Palearctic Regions
tropical forests, suberemic areas, Mediterranean shrublands		Several unrelated genera of Arecaceae
 Meligethinus apicalis (Grouvelle, 1894)N India (W Bengal), SW China
tropical forests
(unknown)		Unknown
 Meligethinus bisignatus Kirejtshuk, 1980Democratic Republic of Congo, Rwanda
tropical forests and shrublands
(I–II, VII–VIII)
(900–1500 m)		Elaeis guineensis Jacq.
 Meligethinus dolosus Grouvelle, 1919NE South Africa, S Mozambique tropical forests and shrublands
(VIII–X)
(0–500 m)		Phoenix reclinata Jacq.
 Meligethinus gedrosiacus Jelínek, 1981Iran, E Arabian Peninsula
suberemic areas
(IV–V)
(0–1300 m)		Nannorrhops ritchiana (Griffith) Aitch
 Meligethinus grouvellei Kirejtshuk, 1980 (7)Southern and eastern India
tropical forests
(unknown)		Unknown
 Meligethinus hamerlae Sabatelli et al., 2020S Mozambique (Inhaca Island)
tropical forests and shrublands (VIII–X)
(0–20 m)		Phoenix reclinata Jacq.
 Meligethinus humeralis Grouvelle, 1906Angola, Democratic Republic of Congo, Rwanda, Mozambique
tropical forests and shrublands
(I–II, VII–IX)
(0–1300 m)		Phoenix reclinata Jacq.
 Meligethinus kabakovi Kirejtshuk, 1980Vietnam, S China including Taiwan
tropical forests
(II–III)
(0–200 m)		Probably Chuniophoenix spp.
 Meligethinus mondlanei Sabatelli et al., 2020S Mozambique
tropical shrublands
(VIII–X)
(0–20 m)		Phoenix reclinata Jacq.
 Meligethinus muehlei Jelínek, 1992Rwanda
tropical forests
(I–II)
(0–1500 m)		Elaeis guineensis Jacq.
 Meligethinus pallidulus (Erichson, 1843)W Mediterranean areas
Mediterranean maquis
(III–VI)
(0–2200 m)		Chamaerops humilis L
 Meligethinus peringueyi (Grouvelle, 1919)NE South Africa, S Mozambique tropical shrublands
(VIII–X)
(0–500 m)		Phoenix reclinata Jacq.
 Meligethinus plagiatus (Grouvelle, 1894)N India (W Bengal), Vietnam, S China including Taiwan
tropical forests
(IV–VI)
(0–500 m)		Probably Chuniophoenix spp.
 Meligethinus quadricollis Kirejtshuk, 1987N India (Uttarakhand)
tropical forests
(unknown)		Unknown
 Meligethinus singularis (Grouvelle, 1919)NE South Africa
tropical shrublands
(unknown)		Probably Phoenix reclinata Jacq. or Hyphaene petersiana Klotzsch ex Mart.
 Meligethinus sp. 1 (Audisio et al., unpublished) (8)South Africa (Eastern Cape)
tropical forests
(XI)
(0–200 m)		Probably Jubaeopsis caffra Becc. or Hyphaene petersiana Klotzsch ex Mart.
 Meligethinus sp. 2 (Audisio et al., unpublished) (8)E Madagascar
tropical forests
(II)
(1000 m)		Unknown, probably Dypsis sp. or Ravenea sp.
 Meligethinus suffusus Kirejtshuk, 1980Democratic Republic of Congo, Mozambique, NE South Africa
tropical forests
(I–V, VIII–X)
(0–2000 m)		Phoenix reclinata Jacq. and likely other forest Arecaceae
 Meligethinus tschungseni Kirejtshuk, 1987S and Central China, N Vietnam, NE India, Japan
subtropical forests
(IV–VII)
(100–2000 m)		Trachycarpus fortunei (Hook.) H. Wendl.
 Meligethinus zimbabwensis Kirejtshuk, 2011W Zimbabwe
subtropical forests
(XII)
(600–800 m)		Probably Phoenix reclinata Jacq. or Hyphaene petersiana Klotzsch ex Mart
(1) The recent re-examination by co-author PA of the type material of Prianella binotata Lechanteur, 1955 [Lechanteuria binotata (Lechanteur, 1955)], Microporum corbisieri Kirejtshuk, 1980, and Microporum interruptum Kirejtshuk, 1980 (deposited in the Royal Museum for Central Africa, Belgium—MRAC) confirmed the clear generic distinction of the African genus Lechanteuria S. Endrödy-Younga, 1978. The previously proposed synonymy with Microporum C. Waterhouse, 1876 (whose species are restricted to Madagascar, the Comoros Islands, and Aldabra, and are associated with Pandanaceae) was incorrectly introduced by Kirejtshuk and coauthors [40,53,66]. Furthermore, the two above listed species of Microporum described by Kirejtshuk [53] from the former Zaire should also be reassigned to Lechanteuria. These taxonomic revisions will be formally addressed in a forthcoming article on the higher systematics of the Meligethinae (Audisio et al., in prep.). (2) Based on the same original source [MRAC], various authors [15,53,64] reported that some specimens of Lechanteuria were collected on fruits of Treculia engleriana (now Treculia africana Decne. ex Trécul; Moraceae). Given that no Meligethinae are known be carpophagous in any way, at least during the larval stage, two scenarios may be proposed: (1) the presence of Lechanteuria adults on Treculia fruits was incidental, possibly related to the intake of sugary exudates in the absence of flowering structures from their true host plants, likely Arecaceae; (2) the collectors may have misidentified the globular Treculia inflorescences as fruits. In this latter case, it cannot be excluded that Moraceae may indeed serve as larval host plants for Lechanteuria species; if so, members of this genus, morphologically closely related to others strictly associated with palms, may actually have experienced a further “host jump” to Moraceae. (3) This small-sized mountain species, recently discovered in Guinea, will be described in a forthcoming publication by Audisio et al. (unpublished data). (4) This newly discovered species from Indonesia will be described in a forthcoming publication by Jelínek et al. (unpublished data). (5) These two highly distinctive undescribed species—the second one notable for the exceptional development of the head and antennae in males—were recently discovered in the border region between southwestern China and eastern Arunachal Pradesh, northeastern India. They will be described in a forthcoming publication by Liu et al., following an upcoming research mission to southwestern China aimed at identifying the host plant of the second species, and collecting fresh material for molecular analyses. (6) Some distinctive morphological traits observed in Kabakovia nepalensis and in the African species of Kabakovia—one described from Ivory Coast as K. ivoriensis by Kirejtshuk and Kirejtshuk [40]—and another one, closely related to the latter, recently discovered in museum material from Uganda (to be treated in a forthcoming publication by Audisio et al.) (Figure 4), suggest that these taxa may represent a lineage closely related to, but perhaps distinct from, the true Indochinese Kabakovia (K. latipes). (7) The taxonomic position of this Oriental taxon will be thoroughly discussed in an upcoming revision of Meligethinus (Liu et al., in prep.). (8) These new species from eastern South Africa (Eastern Cape) and Eastern Madagascar will be described in the aforementioned forthcoming revision of the genus Meligethinus (Liu et al., in prep.).
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Liu, M.; Che, J.; Sabatelli, S.; Gardini, P.; Fattorini, S.; Lasoń, A.; Jelínek, J.; Audisio, P. Palms (Arecaceae) and Meligethinae (Coleoptera, Nitidulidae): A Long Evolutionary Journey. Plants 2025, 14, 2487. https://doi.org/10.3390/plants14162487

AMA Style

Liu M, Che J, Sabatelli S, Gardini P, Fattorini S, Lasoń A, Jelínek J, Audisio P. Palms (Arecaceae) and Meligethinae (Coleoptera, Nitidulidae): A Long Evolutionary Journey. Plants. 2025; 14(16):2487. https://doi.org/10.3390/plants14162487

Chicago/Turabian Style

Liu, Meike, Jinting Che, Simone Sabatelli, Pietro Gardini, Simone Fattorini, Andrzej Lasoń, Josef Jelínek, and Paolo Audisio. 2025. "Palms (Arecaceae) and Meligethinae (Coleoptera, Nitidulidae): A Long Evolutionary Journey" Plants 14, no. 16: 2487. https://doi.org/10.3390/plants14162487

APA Style

Liu, M., Che, J., Sabatelli, S., Gardini, P., Fattorini, S., Lasoń, A., Jelínek, J., & Audisio, P. (2025). Palms (Arecaceae) and Meligethinae (Coleoptera, Nitidulidae): A Long Evolutionary Journey. Plants, 14(16), 2487. https://doi.org/10.3390/plants14162487

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