Variación espacio-temporal de la diversidad de escarabajos Geadephaga (Coleoptera: Carabidae, Cicindelidae) en el bosque seco tropical del Caribe colombiano / Spatio-temporal variation in the diversity of Geadephaga beetles (Coleoptera: Carabidae, Cicindelidae), in the tropical dry forest of the Colombian Caribbean

Resumen Introducción: El uso de artrópodos en estudios ecológicos en el bosque seco tropical (Bs-T) de Colombia se centra mayormente en arañas, mariposas, hormigas y escarabajos coprófagos; por lo tanto, es necesario comprender como es la dinámica estacional de otros grupos como Geadephaga en este ecosistema. Objetivo: Evaluar la variación espacio-temporal y el efecto de las condiciones ambientales sobre la diversidad de las comunidades de Geadephaga en dos fragmentos de Bs-T en el Caribe colombiano. Métodos: El estudio se llevó a cabo en cuatro eventos de muestreo entre febrero y junio de 2018; cada uno con una duración de cuatro días y cuatro noches. En cada localidad (Reserva Campesina La Montaña = RCM y Reserva La Flecha = RLF), se marcaron cuatro estaciones distanciadas 350 m, con parcelas de 50×50 m. En el centro de cada parcela se instaló una trampa de luz, mientras que en los cuatro vértices se instalaron trampas de caída, y se realizó captura manual, cernido de hojarasca y perturbación de follaje. Resultados: Se capturó un total de 348 ejemplares de Carabidae y 114 de Cicindelidae. La riqueza y la abundancia presentaron los valores más bajos durante el período seco, mientras que los mayores valores se observaron durante el período de lluvias, en ambos fragmentos. Tetracha affinis (Dejean, 1825) fue la especie más abundante en la RCM durante el período lluvioso. Conclusiones: La variación de la riqueza y abundancia de Geadephaga responde a un patrón estacional en ambos fragmentos. Se encontró una amplia disimilitud entre las comunidades de Geadephaga de ambos fragmentos, pese a tener condiciones ambientales parecidas.

Abstract Introduction: The use of arthropods in ecological studies in the tropical dry forest (TDF) of Colombia focused mainly on spiders, butterflies, ants, and dung beetles; therefore, it is necessary to understand the seasonal dynamics of the other groups such as Geadephaga in this ecosystem. Objective: To evaluate the spatio-temporal variations and the effect of environmental conditions on the diversity of the Geadephaga communities in two TDF fragments in the Colombian Caribbean. Methods: This study was conducted during four sampling events between February and June 2018, each lasting four days, and four nights. Four sampling stations were selected in each locality (Reserva Campesina La Montaña = RCM and Reserva La Flecha = RLF), separated 350 m one from another, with square plots of 50 × 50 m. A light trap was installed in the center of each square, while pitfall traps were installed in the four vertices, and manual capture, beating sheets and leaf litter sieve were carried out. Results: A total of 348 Carabidae and 114 of Cicindelidae were captured. In both fragments, the richness and abundance presented the lowest values in dry season, while the highest values were observed during the rainy season. Tetracha affinis (Dejean, 1825) was the most abundant species in RCM during rainy season. Conclusions: The richness variation and abundance of Geadephaga corresponds to a seasonal pattern at both locations. A high dissimilarity between the communities of Geadephaga from the two fragments was found, despite having similar environmental conditions.

DNA but not always morphology help to recognise monophyletic genera within 'Cercyon' terrestrial water scavenger beetles: a case study of Asiacyon gen. nov. (Coleoptera: Hydrophilidae).

DNA-based studies have revealed that the terrestrial water scavenger beetle genus Cercyon Leach, 1817 (Coleoptera: Hydrophilidae: Sphaeridiinae: Megasternini) is polyphyletic, grouping similarly looking but unrelated species that were not assigned to other genera due to the absence of unusual morphological characters. In this study, we analyse the morphology, DNA data and species diversity of one of the Asian clades of 'Cercyon ' to test whether a natural, phylogeny-based generic classification can be established. We add DNA data (five nuclear and three mitochondrial fragments) for additional species and specimens of the clade to test its monophyly and reveal phylogenetic relationships among species. We perform a detailed morphological study of all species, including SEM micrographs, to reveal synapomorphies of the DNA-based clades. We demonstrate that the lineage, described here as Asiacyon Mai, Jia, Ryndevich & Fikácek, gen. nov., is strongly supported by DNA data, has limited distribution (eastern Asia), and its species share similar biology (inhabiting fresh or decaying plant tissues), though it can be only diagnosed by a combination of plesiomorphic characters. A detailed treatment is provided for the Chinese species, including species diagnoses, illustrations of habitus and male genitalia, (re)descriptions and a key to species. A total of 14 Chinese species are recognised, of which 11 are described as new: Asiacyon pax sp. nov. (Guangdong, Hong Kong, Hunan), A. pseudincretus sp. nov. (Anhui, Jiangxi, Taiwan, Zhejiang), A. vicincretus sp. nov. (Guangdong, Guangxi), A. zhengyucheni sp. nov. (Yunnan), A. huilanae sp. nov. (Yunnan), A. cornipenis sp. nov. (Yunnan), A. belousovi sp. nov. (Yunnan), A. liangchengi sp. nov. (Yunnan), A. paraequalis sp. nov. (Yunnan), A. pengzhongi sp. nov. (Hunan) and A. xiuzhenae sp. nov. (Hainan, Yunnan). Three Chinese species previously classified in Cercyon are transferred to Asiacyon : A. incretus (d'Orchymont, 1941), comb. nov., A. primoricus (Ryndevich & Prokin, 2017), comb. nov. (newly recorded from China) and A. indicus (d'Orchymont, 1926), comb. nov. (newly recorded from China and Laos). Additionally, seven Asian species previously classified in Cercyon are transferred to Asiacyon based on their external morphology, but not studied in detail: A. aequalis (Sharp, 1884), comb. nov., A. conjiciens (Walker, 1858), comb. nov., A. dilutus (Régimbart, 1903), comb. nov., A. placidus (Sharp, 1884), comb. nov., A. pseudodilutus (Satô, 1979), comb. nov., A. retius (Ryndevich & Prokin, 2017), comb. nov., and A. rubicundus (Sharp, 1884), comb. nov. In total, the genus now comprises 21 named species and several undescribed species from India, Myanmar and Indonesia. ZooBank: urn:lsid:zoobank.org:pub:E3C949A0-34E4-46EF-BA6A-2CD048D583B2.

Integrative taxonomy of Teucriogethes pollen beetles (Coleoptera: Nitidulidae: Meligethinae), with implications on the systematics of the genus Teucrium (Lamiaceae).

In highly specialised phytophagous insects, important insights on phylogeny of the involved insect group can be often inferred from the evolutionary history of their host plants, and vice-versa, as in the case for a new, peculiar species of pollen beetles, recently discovered in Central China (Hubei Province). This new species is described herein as Teucriogethes huangae Liu & Audisio, sp. nov., and information on its ecology and systematic position is provided. The new species, associated as larvae with a strongly isolated member of the genus Teucrium L. (Lamiaceae), T. ornatum Hemsl., exhibiting a problematic taxonomic position, represents in turn an isolated and morphologically rather aberrant taxon in its lineage, probably the largest in size (2.2-2.8mm), and the first endemic representative of its genus in the whole Eastern Palaearctic. An updating of the taxonomic assessment of members of Teucriogethes and on possible evolutionary relationships with their larval host plants, based on an integrative taxonomy approach, is finally presented. A key to identification of all known species is also introduced. ZooBank: urn:lsid:zoobank.org:pub:E349044B-29A5-416C-85CA-56143C7A29BE.

Three Mitochondrial Genomes of Chrysochroinae (Coleoptera, Buprestidae) and Phylogenetic Analyses.

Three mitochondrial genomes of Chrysochroinae (Buprestidae) were sequenced and analyzed. The mitogenomes of the genera Catoxantha and Nipponobuprestis are first reportedand Chrysochroa opulenta is a first record for China. The complete mitogenomes of Catoxantha luodiana, Nipponobuprestis guangxiensis and Chrysochroa opulenta exhibit striking similarities in their lengths and composition. Specifically, their lengths are 15,594 bp, 15,775 bp and 15,587 bp, respectively. Each of these genomes encodes 37 typical mitochondrial genes. The overwhelming majority of protein-coding genes (PCGs) have the typical ATN (ATT, ATA, ATG or ATC) as the start codon and terminate with TAR (TAA or TAG) as the stop codon or an incomplete stop codon T-. Among the three mitogenomes, Leu2, Ser2 and Phe were the most frequently encoded amino acids. In the PCGs, the Ka/Ks ratio of cox1 is the lowest, whereas atp6 has the highest value. This suggests that cox1 can be used as a molecular barcode for species delimitation and phylogeny in Chrysochroinae. The phylogenetic results showed that C. luodiana and two Chrysochroa species formed a clade. Based on the topology of the phylogenetic tree, the genus Catoxantha should be reassigned as a subgenus of Chrysochroa.

Past and current climate as a driver in shaping the distribution of the Longitarsus candidulus species group (Coleoptera: Chrysomelidae).

Longitarsus candidulus (Foudras) is a thermophilic flea beetle species widely distributed in the Mediterranean Basin and associated with Daphne gnidium L. and Thymelaea hirsuta (L.). Longitarsus laureolae Biondi and Longitarsus leonardii Doguet, phylogenetically closely related to L. candidulus, show together a peculiar and rare disjunct distribution along the central-southern Apennines and the Cantabrian-Pyrenean mountain system, respectively. Both are associated with Daphne laureola L. in mesophilic habitats. We used "ecological niche modeling" to infer the Pleistocene dynamics in the distribution of the three flea beetle species and their host plants. We interpreted their current distributions, paying particular attention to the presumed time of species divergence as inferred from recent studies. The differentiation of L. laureolae and L. leonardii from L. candidulus likely represents a response to the marked climatic changes during the Late Pliocene. Such a split was likely associated with a trophic niche shift of the laureolae/leonardii ancestor towards the typically mesophilic host plant D. laureola. The subsequent split between L. laureolae and L. leonardii, possibly due at first to the niche competition, was then boosted by an allopatric divergence during the Middle Pleistocene, likely caused by a large area of low environmental suitability for both species, mainly located between the northern Apennines and the south-western Alps.

An unusual Cretaceous beetle with affinity to Anamorphidae (Coleoptera: Coccinelloidea).

Coccinelloid beetles have a sparse fossil record in the Mesozoic. Here, we describe and illustrate an unusual coccinelloid beetle, Yassibum yoshitomii gen. et sp. nov., from mid-Cretaceous Kachin amber. Yassibum stands out within the Coccinelloidea due to its notched profemora and the presence of antennal grooves on the elytral epipleura. Based on our phylogenetic analyses, we suggest that Yassibum is most likely related to the family Anamorphidae. The alternative placements are critically evaluated based on our comparison of the morphology.

The first report of complete mitogenomes of two endangered species of genus Propomacrus (Coleoptera: Scarabaeidae: Euchirinae) and phylogenetic implications.

To understand the mitochondrial genome structure of two endangered and long-armed scarab beetles, Propomacrus davidi and Propomacrus bimucronatus, their complete mitogenomes were sequenced for the first time in this study. The complete mitogenomes of P. davidi and P. bimucronatus were 18, 042 bp and 18, 104 bp in length, respectively. The gene orders of their mitogenomes were highly consistent with other Coleopteran species, and the typical ATN was used as the start codon in most protein coding genes. The incomplete stop codon T was used in cox1, cox2, and nad5, and TAN was used as a complete stop codon in most protein coding genes. All predicted tRNAs could form a typical cloverleaf secondary structure, except that trnS1 lacked the dihydrouridine arm. Based on the maximum likelihood and the Bayesian inference methods, phylogenetic trees of 50 species were reconstructed. The results showed that P. davidi, P. bimucronatus, Cheirotonus jansoni and Cheirotonus gestroi clustered in the same branch, and were the most closely related. The results supported that subfamily Euchirinae is a monophyletic group of Scarabaeidae, which was consistent with the morphological classification. These molecular data enriched the complete mitogenome database of Euchirinae, and improved our understanding of the phylogenetic relationship and evolutionary characteristics of these two endangered species.

New taxonomic insights for Brazilian Syrbatus Reitter (Coleoptera: Staphylinidae: Pselaphinae), including three new species and their mitochondrial genomes.

Here we present a taxonomic treatment for the Brazilian species of Syrbatus (Reitter, 1882), including the description of three new species (Syrbatus moustache Asenjo & Valois sp. nov., Syrbatus obsidian Asenjo & Valois sp. nov. and Syrbatus superciliata Asenjo & Valois sp. nov.) from the Quadrilátero Ferrífero (Minas Gerais, Brazil). In addition, we designated lectotypes for the Brazilian species of species-group 2, Syrbatus centralis (Raffray, 1898), Syrbatus hetschkoi (Reitter, 1888), Syrbatus hiatusus (Reitter, 1888), Syrbatus transversalis (Raffray, 1898), and Syrbatus trinodulus (Schaufuss, 1887), besides recognizing the holotype for Syrbatus brevispinus (Reitter, 1882), Syrbatus bubalus (Raffray, 1898), and Syrbatus grouvellei (Raffray, 1898). The mitochondrial genomes (mitogenomes) of the three new species are presented, for which we present the phylogenetic placement among Staphylinidae with previously published data.

Genomic, morphological and physiological data support fast ecotypic differentiation and incipient speciation in an alpine diving beetle.

An intricate interplay between evolutionary and demographic processes has frequently resulted in complex patterns of genetic and phenotypic diversity in alpine lineages, posing serious challenges to species delimitation and biodiversity conservation planning. Here we integrate genomic data, geometric morphometric analyses and thermal tolerance experiments to explore the role of Pleistocene climatic changes and adaptation to alpine environments on patterns of genomic and phenotypic variation in diving beetles from the taxonomically complex Agabus bipustulatus species group. Genetic structure and phylogenomic analyses revealed the presence of three geographically cohesive lineages, two representing trans-Palearctic and Iberian populations of the elevation-generalist A. bipustulatus and another corresponding to the strictly-alpine A. nevadensis, a narrow-range endemic taxon from the Sierra Nevada mountain range in southeastern Iberia. The best-supported model of lineage divergence, along with the existence of pervasive genetic introgression and admixture in secondary contact zones, is consistent with a scenario of population isolation and connectivity linked to Quaternary climatic oscillations. Our results suggest that A. nevadensis is an alpine ecotype of A. bipustulatus, whose genotypic, morphological and physiological differentiation likely resulted from an interplay between population isolation and local altitudinal adaptation. Remarkably, within the Iberian Peninsula, such ecotypic differentiation is unique to Sierra Nevada populations and has not been replicated in other alpine populations of A. bipustulatus. Collectively, our study supports fast ecotypic differentiation and incipient speciation processes within the study complex and points to Pleistocene glaciations and local adaptation along elevational gradients as key drivers of biodiversity generation in alpine environments.

Elucidating Scarab Divergence in an Evolutionary-Ecological Context through the Comprehensive Analysis of the Complete Mitogenome of Anomala.

Anomala Samouelle, 1819 is one of the specious genera of Coleoptera, with over 1000 known species, and includes some of the most destructive pests of crops or forests. Morphological convergence is a common phenomenon within this genus, making the identification of closely related species very difficult. To explore the phylogenetic placement of Anomalini and provide a basis for the classification and identification of Anomala, we comparatively analyzed the complete mitogenome of three Anomala species (A. exoleta, A. perplexa diana, and A. praecoxalis). Based on all accessible mitogenome data, we performed comparative mitochondrial genomics analysis of this genus and reconstructed the phylogenetic relationships of Scarabaeidae based on two datasets (protein-coding genes and amino acids) and two methods (Bayesian approach and maximum likelihood). The phylogenetic relationships found in this study highly support that the groups of Aphodiinae, Cetoniinae, Dynastinae, Rutelinae and Scarabaeinae are monophyletic. Interestingly, the phylogenetic clustering relationship was highly consistent with the Scarabaeidae diet, indicating that the herbivorous species and dung-eating species are clustered separately. The phylogenetic tree showed that the subfamily Melolonthinae and the genus Anomala are not monophyletic, suggesting that these two groups should be further revised with more data.

Taxonomic Revision of the Dichotomius mormon (Ljungh, 1799) Species Group (Coleoptera: Scarabaeidae: Scarabaeinae), with a Description of a New Species from Bolivia.

Dichotomius Hope, 1838 (Coleoptera: Scarabaeidae: Scarabaeinae) is a very abundant and diverse genus of dung beetles of the New World ecosystems, with about 190 species, distributed in four subgenera. Luederwaldt (Separata Rev Mus Paul 14: 3-13 1929) proposed the division of subgenera into sections (now species groups) based mainly on characters of external morphology. Based on Luederwaldt's proposal, progress has been made in recent years in the taxonomic revision of the genus; however, inconsistencies have been found in the subgeneric division and species groups proposed by this author. Based on the external morphology and the male genital organ of the all type material and other material deposited in fifteen entomological collections, in this paper, the redefinition and taxonomic revision of the Dichotomius mormon species group is carried out. The new definition of the group and the species key are presented. Five species are included in the group: Dichotomius conicollis (Blanchard, 1846) (Bolivia), Dichotomius larseni sp. nov. (Bolivia), Dichotomius mormon (Ljungh, 1799) (Argentina, Brazil, and Paraguay), Dichotomius ohausi (Luederwaldt, 1923) (Brazil, Colombia, Ecuador, and Peru), and Dichotomius talaus (Erichson, 1847) stat. rev. (Bolivia, and Peru). The lectotypes for D. conicollis, Copris ephialtes Mannerheim, 1829, Copris nasuta Castelnau, 1840, Copris protensus Perty, 1830, D. ohausi, and D. talaus were designated. For each of the species that are included in the group, the following information is presented: taxonomic history, species' citation in published literature, description or redescription of males and females, list of material examined, photographs of the external morphology, illustrations of male genital organ and its endophallites, and distribution map.

Development, survival and description of the life stages of Zatrephina lineata (Coleoptera: Chrysomelidae) fed on Ipomoea pes-caprae leaves.

Zatrephina lineata (Coleoptera: Chrysomelidae) is a phytophagous insect, mainly of plants of the genera Ipomoea and Mikania. The objective was to study the development, survival and to describe the life stages of Z. lineata fed on leaves of Ipomoea pes-caprae. Biological observations were made daily with the aid of a stereoscopic microscope and the instars of this insect identified by the exuvia left between one moulting and the next. The duration of development and survival of the egg, larva and pupa stages and the first, second, third, fourth and fifth instars and of the nymph stage of Z. lineata differed, but not between sexes of this insect. The duration of development of Z. lineata was longer in the larval stage and in the fifth instar, and its survival greater in the egg and pupa stages and in the first and fifth instars. Zatrephina lineata eggs, cream-colored, are ellipsoid and deposited in groups on the adaxial surface of older I. pes-caprae leaves. The larvae of this insect go through five instars, with the first three being gregarious with chemo-behavioral defenses. The exarated pupae of Z. lineata, light yellow in color and with an oval shape flattened dorsoventrally, attach to the abaxial surface of the I. pes-caprae leaves. The shape of adults of this insect is oval, straw yellow in color with lighter longitudinal stripes and females are slightly larger than males.

A New Species of Megaceropsis Dechambre, 1976 and a New Record of Megaceropsis quadridentata Dechambre, 1976 (Coleoptera, Melolonthidae, Dynastinae, Oryctini).

Megaceropsis Dechambre, 1976 (Coleoptera, Melolonthidae, Dynastinae, Oryctini) is a South American genus with two known species until now: Megaceropsis quadridentata Dechambre, 1976 and Megaceropsis lecourti Dechambre, 1996. We describe a third species herein: Megaceropsis kleytoni sp. nov., from Brazil. Illustrations, a distributional map, and an identification key including all Megaceropsis species are provided. Additionally, a first record of M. quadridentata from Brazil is presented.

Climate change will lead to range shifts and genetic diversity losses of dung beetles in the Gobi Desert and Mongolian Steppe.

Desertification is known to be a major threat to biodiversity, yet our understanding of the consequent decline in biodiversity remains insufficient. Here, we predicted climate change-induced range shifts and genetic diversity losses in three model dung beetles: Colobopterus erraticus, Cheironitis eumenes, and Gymnopleurus mopsus, distributed across the Gobi Desert and Mongolian Steppe, areas known for desertification. Phylogeographic analyses of mitochondrial COI sequences and species distribution modeling, based on extensive field investigations spanning 14 years, were performed. Species confined to a single biome were predicted to contract and shift their distribution in response to climate change, whereas widespread species was predicted to expand even if affected by range shifts. We indicated that all species are expected to experience significant haplotype losses, yet the presence of high singleton frequencies and low genetic divergence across geographic configurations and lineages mitigate loss of genetic diversity. Notably, Cheironitis eumenes, a desert species with low genetic diversity, appears to be the most vulnerable to climate change due to the extensive degradation in the Gobi Desert. This is the first study to predict the response of insects to desertification in the Gobi Desert. Our findings highlight that dung beetles in the Gobi Desert and Mongolian Steppe might experience high rates of occupancy turnover and genetic loss, which could reshuffle the species composition.

The South American genus Cnemalobus (Coleoptera: Carabidae: Cnemalobini): phylogeny and biogeographic analysis with the description of four new species from extra-Andean Patagonian mountains.

The carabid beetle Cnemalobus Guérin-Ménéville, 1838 inhabits high- and lowland grasslands of southern South America. The highest diversity is found in the Patagonian Steppe, where distribution patterns are associated with latitude and elevation. Northern Patagonia, a large volcanic region with a complex geoclimatic history, exhibits elevated grades of endemism. However, a great deal remains unknown regarding diversification and biogeographical patterns for most of the endemic groups. We describe new Cnemalobus species restricted to isolated volcanoes from these extra-Andean mountain systems. We assess the phylogenetic relationships by updating the phylogeny of the genus and conduct a Bayesian binary Markov chain-Monte Carlo (MCMC) analysis on the resulting phylogenetic tree to discuss the biogeographical distribution patterns. We also provide a taxonomic key to all currently known species of Cnemalobus from the Patagonian Steppe. Our phylogenetic analysis supports the monophyly of the new species Cnemalobus tromen sp. nov., Cnemalobus silviae sp. nov., Cnemalobus aucamahuida sp. nov. and Cnemalobus domuyo sp. nov. grouped with C. diamante and C. nevado , referred to as the 'Extra-Andean' mountain lineage. Biogeographical analysis recognises vicariant events as the most plausible explanation for the allopatric distributions of the new species. We hypothesise that these vicariant events could be related to climatic barriers that likely promoted speciation processes by generating geographical isolation in ancestral populations. Our findings contribute significantly to the biogeographical understanding of the Patagonian volcanic region, prompting new inquiries to unravel the speciation processes of the endemic biota in extra-Andean mountain systems. ZooBank: urn:lsid:zoobank.org:pub:6A7585E8-5006-45BC-A1A3-F874F18A6049.

Differential amplification and contraction of satellite DNAs in the distinct lineages of the beetle Euchroma gigantea.

Satellite DNA (satDNA) consists of tandem repeat sequences that typically evolve rapidly through evolutionary mechanisms, including unequal crossover, transposition events, and others. The evolutionary history of Euchroma gigantea is marked by complex chromosomal evolution between lineages, making this species an interesting model for understanding satDNA evolution at intraspecies level. Therefore, our aim was to comprehend the potential contribution of satDNAs to the greater chromosomal differentiation of evolutionary lineages in E. gigantea by investigating the differential patterns of amplification and contraction of the repeats. To achieve this, we employed de novo identification of satDNA using RepeatExplorer and TAREAN, allowing the satellitome characterization between lineages. A total of 26 satDNA families were identified, ranging from 18 to 1101 nucleotides in length, with most families being shared between individuals/lineages, as predicted by the library hypothesis, except for the satDNA EgiSat21-168 that was absent for Northeast Lineage. The total satDNA content of the individuals was less than 11.2%, and it appeared to increase in two directions following the chromosomal evolution model. Thirteen satDNAs exhibited different patterns of amplification, and nine ones were contracted among individuals. Additionally, most repeats showed a divergence of about 10% for these satDNAs, indicating satellitome differentiation for each lineage/individual. This scenario suggests that the expansion of the satellitome occurred differentially among individuals/lineages of E. gigantea, with the contribution of various DNA turnover mechanisms after geographical isolation, and that they could be involved with karyotype evolution.

The first mitogenomic phylogenetic framework of Dorcus sensu lato (Coleoptera: Lucanidae), with an emphasis on generic taxonomy in Eastern Asia.

BACKGROUND: Dorcus stag beetles in broad sense are one of the most diverse group in Lucanidae and important saproxylic insects playing a crucial role in nutrient recycling and forest biomonitoring. However, the dazzling morphological differentiations have caused numerous systematic confusion within the big genus, especially the puzzlingly generic taxonomy. So far, there is lack of molecular phylogenetic study to address the chaotic situation. In this study, we undertook mitochondrial genome sequencing of 42 representative species including 18 newly-sequenced ones from Eastern Asia and reconstructed the phylogenetic framework of stag beetles in Dorcus sensu lato for the first time. RESULTS: The mitogenome datasets of Dorcus species have indicated the variable mitogenomic lengths ranged from 15,785 to 19,813 bp. Each mitogenome contained 13 PCGs, 2 rRNAs, 22 tRNAs, and a control region, and all PCGs were under strong purifying selection (Ka/Ks < 1). Notably, we have identified the presence of a substantial intergenic spacer (IGS) between the trnAser (UCN) and NAD1 genes, with varying lengths ranging from 129 bp (in D. hansi) to 158 bp (in D. tityus). The mitogenomic phylogenetic analysis of 42 species showed that Eastern Asia Dorcus was monophyletic, and divided into eight clades with significant genetic distance. Four of them, Clade VIII, VII, VI and I are clustered by the representative species of Serrognathus Motschulsky, Kirchnerius Schenk, Falcicornis Séguy and Dorcus s.s. respectively, which supported their fully generic positions as the previous morphological study presented. The topology also showed the remaining clades were distinctly separated from the species of Dorcus sensu lato, which implied that each of them might demonstrate independent generic status. The Linnaeus nomenclatures were suggested as Eurydorcus Didier stat. res., Eurytrachellelus Didier stat. res., Hemisodorcus Thomson stat. res. and Velutinodorcus Maes stat. res. For Clade V, IV, III and II respectively. CONCLUSION: This study recognized the monophyly of Dorcus stag beetles and provided a framework for the molecular phylogeny of this group for the first time. The newly generated mitogenomic data serves as a valuable resource for future investigations on lucanid beetles. The generic relationship would facilitate the systematics of Dorcus stag beetles and thus be useful for exploring their evolutionary, ecological, and conservation aspects.

Chromosomal inversions from an initial ecotypic divergence drive a gradual repeated radiation of Galápagos beetles.

Island faunas exhibit some of the most iconic examples where similar forms repeatedly evolve within different islands. Yet, whether these deterministic evolutionary trajectories within islands are driven by an initial, singular divergence and the subsequent exchange of individuals and adaptive genetic variation between islands remains unclear. Here, we study a gradual, repeated evolution of low-dispersive highland ecotypes from a dispersive lowland ecotype of Calosoma beetles along the island progression of the Galápagos. We show that repeated highland adaptation involved selection on multiple shared alleles within extensive chromosomal inversions that originated from an initial adaptation event on the oldest island. These highland inversions first spread through dispersal of highland individuals. Subsequent admixture with the lowland ecotype resulted in polymorphic dispersive populations from which the highland populations evolved on the youngest islands. Our findings emphasize the significance of an ancient divergence in driving repeated evolution and highlight how a mixed contribution of inter-island colonization and within-island evolution can shape parallel species communities.

Early evolution of Anamorphidae (Coleoptera: Coccinelloidea): the oldest known anamorphid beetles from Upper Cretaceous amber of northern Myanmar and the first report of potential glandular pores in the family.

In order to place newly discovered fossil taxa (Palaeosymbius gen. nov. with P. groehni and P. mesozoicus spp. nov.) from the mid-Cretaceous amber from northern Myanmar, we investigated the relations of extant and extinct lineages of the coccinellid group of Coccinelloidea with emphasis on the family Anamorphidae. We assembled a taxonomic sampling of 34 taxa, including 15 genera and 19 species of Anamorphidae, the most comprehensive sampling of Anamorphidae at the generic level in a phylogenetic analysis. A morphological dataset of 47 characters was built as well as a molecular alignment of 7140 bp including fragments of eight genes (12S, 16S, 18S, 28S, COI, COII, H3 and CAD). Five anamorphid and one endomychid species were sequenced for the first time and added to the dataset. We performed parsimony-based analysis of the morphological dataset and Bayesian inference analysis of the combined matrix (morphological plus molecular data). Our results confirm that Palaeosymbius belongs to Anamorphidae and represents the oldest known member of this family so far. Among Anamorphidae, Symbiotes (with extant and known Eocene species) was recovered as the most probable closest relative of Palaeosymbius. Our morphological studies additionally revealed the presence of probable glandular openings in the anterolateral corners of the pronotal margins in Asymbius sp. and Anamorphus sp., representing the first report of secretory openings in the family Anamorphidae. Similar openings are found in other cucujiform beetles such as Cryptophagidae and Boganiidae with possible defensive purposes.

Testing and optimizing metabarcoding of iDNA from dung beetles to sample mammals in the hyperdiverse Neotropics.

Over the past few years, insects have been used as samplers of vertebrate diversity by assessing the ingested-derived DNA (iDNA), and dung beetles have been shown to be a good mammal sampler given their broad feeding preference, wide distribution and easy sampling. Here, we tested and optimized the use of iDNA from dung beetles to assess the mammal community by evaluating if some biological and methodological aspects affect the use of dung beetles as mammal species samplers. We collected 403 dung beetles from 60 pitfall traps. iDNA from each dung beetle was sequenced by metabarcoding using two mini-barcodes (12SrRNA and 16SrRNA). We assessed whether dung beetles with different traits related to feeding, nesting and body size differed in the number of mammal species found in their iDNA. We also tested differences among four killing solutions in preserving the iDNA and compared the effectiveness of each mini barcode to recover mammals. We identified a total of 50 mammal OTUs (operational taxonomic unit), including terrestrial and arboreal species from 10 different orders. We found that at least one mammal-matching sequence was obtained from 70% of the dung beetle specimens. The number of mammal OTUs obtained did not vary with dung beetle traits as well as between the killing solutions. The 16SrRNA mini-barcode recovered a higher number of mammal OTUs than 12SrRNA, although both sets were partly non-overlapping. Thus, the complete mammal diversity may not be achieved by using only one of them. This study refines the methodology for routine assessment of tropical mammal communities via dung beetle 'samplers' and its universal applicability independently of the species traits of local beetle communities.