Genome sequencing reveals extraordinary cephalic horns in the Madagascan dung beetle genus Helictopleurus (Coleoptera, Scarabaeinae) : insight from a revision of fungicola species group

In this study, we test and corroborate the phylogenetic position of Heterosyphus within Helictopleurus using mitogenomes and nuclear loci. Our recent samplings revealed that males of the former Heterosyphus sicardi Paulian, 1975 (today under Helictopleurus d'Orbigny, 1915) have extraordinary bilateral clypeal horns which are exclusive within the genus. We provide a taxonomic review of the fungicola species group of Helictopleurus and discuss the systematic position of H. sicardi within the group. The male phenotype of H. sicardi is described and photographs of the body and genitalia of the members of the fungicola group are given, as well as a diagnostic key to species of the group. Helictopleurus fungicola peyrierasi is considered to be a distinct species within the genus (H. peyrierasi stat. rest.). Helictopleurus pluristriatus d'Orbigny, 1915 syn. nov. is established as a junior synonym of H. fungicola (Fairmaire, 1899).Peer reviewe

Paleogene forest fragmentation and out-of-Africa dispersal explain radiation of the Paleotropical dung beetle tribe Epactoidini trib. nov. (Coleoptera Scarabaeinae)

Paleotropical clades with largely disjunct distributions are ideal models for biogeographic reconstructions. The dung beetle genera Grebennikovius Mlambo, Scholtz & Deschodt, Epactoides Olsouffief and Ochicanthon Vaz-de-Mello are distributed in Tanzania, Madagascar and Reunion, and the Oriental region, respectively. We combine morphology and molecular dataset to reconstruct the phylogenetic relationships between these taxa. Our analyses corroborate previous hypotheses of monophyly of the group, which is here described as new tribe Epactoidini trib. nov. Grebennikovius is recovered as sister to Epactoides, while Ochicanthon emerges as sister to them both. The disjunct distribution of our focal clade is unusual within the subfamily Scarabaeinae. Bayesian divergence time estimates and ancestral range reconstructions indicate an African origin of the crown group of the tribe Epactoidini trib. nov. in the early mid Eocene, ca. 46 Ma. The divergence between Epactoides and its sister is dated to 32.3 Ma, while the crown age for the genus Ochicanthon is dated to 27 Ma. We investigate the factors that may have shaped the current distribution of the tribe Epactoidini trib. nov. The formation of the Gomphotherium landbridge, along with favourable environmental conditions would have allowed dry-intolerant organisms, such as Ochicanthon, to disperse out of Africa. Remarkable climatic stability of the Eastern Arc Mountains was critical for the retention of the monotypic genus Grebennikovius. We suggest two subsequent overwater dispersal events: the migration of the most recent common ancestor (MRCA) of Epactoides from Africa to Madagascar (32.3-29.5 Ma); the lately dispersal of the MRCA of the today's extinct Epactoides giganteus Rossini, Vaz-de-Mello & Montreuil to Reunion island from Madagascar (3.4 Ma). We suggest that the high potential of dispersal of Epactoidini trib. nov. dung beetles and the strict association to forest habitat might have triggered two major radiations, one in Madagascar and one in the Oriental Region.Peer reviewe

Microallopatric speciation in the relict dung beetle genus Grebennikovius (Coleoptera: Scarabaeidae) in the Eastern Arc Mountains

The Eastern Arc Mountains (EAMs) in Tanzania and Kenya are renowned for their exceptional species endemism often restricted to isolated mountain blocks. Forest fragmentation during the Pliocene–Pleistocene played a sig- nificant role in shaping the EAMs’ biodiversity by facilitating allopatric speciation between different mountains. However, only a few studies focused on species diversification within the same mountain block. In this article, we investigated the taxonomy and evolution of the dung beetle genus Grebennikovius, endemic to the Uluguru Mountains. Our goal was to unravel factors promoting allopatric speciation within a confined geographic area like the Ulugurus. We used an integrative taxonomic approach, combining phenotypic data and COI barcodes to delimit species and reconstructed a timetree of the genus. Molecular and morphological evidence consistently recovered 4 distinct Grebennikovius species, of which 3 are new to science: G. armiger n. sp., G. basilewskyi (Balthasar, 1960), G. lupanganus n. sp., and G. pafelo n. sp. Grebennikovius represents a rare case of microal- lopatry, with all species occurring in close proximity within different regions of the limited Uluguru forest (∼230 km2). We infer that speciation was driven by the interplay between climate fluctuations during the Miocene and mid-Pleistocene, Uluguru topography, and the stability of rainforest ecological conditions. The latter fac- tor probably favored the loss of wings and a specialization for Uluguru microhabitats, reinforcing population isolation and divergence. This study highlights a unique instance of diversification resulting from small-scale speciation events, providing valuable insights into the evolution of Eastern African rainforest arthropods and underscoring the importance of microhabitats conservation

Miocene uplift and Pleistocene forest connectivity drove the evolution of large-bodied Afrotropical pill scarabs (Co adleo adptera: Hybosoridae: Afrocloetus and Congomostes)

This study targets the post-Oligocene evolution of low-vagility beetles in wet African forests. Two nominal genera of large-bodied pill scarabs form the focus: the East African Afrocloetus with two nominal species and the Central African Congomostes with three nominal species. Both genera are rarely sampled, particularly Afrocloetus which is known until now from two holotypes collected in 1948 and 1957. Long series of Afrocloetus are newly reported from four Tanzanian localities: Kimboza forest, Kaguru, Rubeho and Udzungwa- the last three belong to the biodiverse chain of the Eastern Arc Mountains. A phylogenetic analysis utilized a matrix consisting of 52 terminals (including five Afrocloetus and two Congomostes) and an alignment of 2,940 bp from one mitochondrial and two nuclear fragments. The analysis recovered both genera as monophyletic and forming the sister clade to the Afrotropical Philharmostes group of genera. Molecular clock analysis of 39 DNA barcodes of both genera estimated their separation within a temporal window (13.0-6.8 Ma) that is fully concurrent with the Miocene uplift of the East African Plateau causing aridification and forest fragmentation. Three Tanzanian localities each support an endemic mitochondrial Afrocloetus clade evolving in allopatry, following the pre-Pleistocene range breakup of their originally widespread ancestor (= first cycle of forest expansion and contraction). Two morphologically and genetically distinct Afrocloetus clades co-exist in Udzungwa- this sympatry is attributed to secondary re-colonization of Udzungwa by the younger and reproductively isolated clade at 2.4-1.2 Ma (= second cycle of forest expansion and contraction). This hypothesised re-colonisation of Udzungwa by flightless beetles coincides with the Pleistocene climatic cycles and suggests temporal connectivity between Rubeho and Udzungwa forests. Adults of Afrocloetus are extensively illustrated, compared among themselves and with those of Congomostes, and their relevant evolutionary markers are discussed. The taxonomy of both nominal and likely synonymous genera is unmodified pending further research. Habitus images, DNA sequences and other supplementary information of all sequenced specimens are available online at dx.doi.org/10.5883/DS-VGDS002 and dx.doi.org/10.5883/DS-VGDS003

Sky islands of the Cameroon Volcanic Line support the westernmost clade of five new Typoderus weevils (Coleoptera: Curculionidae: Molytinae)

Abstract The weevil genus Typoderus is for the first time reported west of the Congo basin. Analysis of 2,136 aligned positions from one mitochondrial and two nuclear fragments revealed a moderately supported clade of five new Cameroonian species: T. amphion sp. nov. (Mt. Oku), T. canthus sp. nov. (Mt. Oku), T. clytius sp. nov. (Mt. Cameroon), T. iphitus sp. nov. (Mt. Kupe) and T. telamon sp. nov. (Mt. Kupe). Molecular clock analysis of 20 DNA barcode fragments using a fixed substitution rate estimated divergences within this clade to be during the Middle to Late Miocene (10.5–5.4 million years ago, MYA), which pre-dates the onset of the Pliocene-Pleistocene global climatic fluctuations and corresponding cycles of African forest size fluctuation. Such relatively old dates are unexpected and might reflect four unavoidable shortcomings of the temporal analysis: 1. undersampled ingroup, 2. scarcity of comparative temporal data for other animal clades from the Cameroon Volcanic Line, 3. oversimplification of a fixed-rate molecular clock approach using a single maternally-inherited protein-coding marker and 4. possible overestimation of comparatively old ages when using largely saturated mitochondrial sequences. Two obscure weevil species from the Republic of the Congo are hypothesized to belong to the genus Typoderus: T. distinctus (Hoffmann, 1968) comb. nov. (from Anchonidium subgenus Neoanchonidium) and T. baloghi (Hoffmann, 1968) comb. nov. (from Anchonidium subgenus Subanchonidium). Three genus-group names are newly synonymized under Typoderus: Entypoderus Voss, 1965 syn. nov. (the only non-nominative subgenus of Typoderus), Neoanchonidium Hoffmann, 1968 syn. nov. (subgenus of Anchonidium) and Subanchonidium Hoffmann, 1968 syn. nov. (subgenus of Anchonidium). Habitus images and other supplementary information of all sequenced specimens are available online at dx.doi.org/10.5883/DS-VGDS005 and dx.doi.org/10.5883/DS-VGDS006

Independent morphological and genetic diversification in close geographic and phylogenetic proximity: Typoderus weevils (Coleoptera) in the Uluguru Mountains, Tanzania

The Eastern Arc Mountains (EAM) of Tanzania form an island-type archipelago of wet and cool rainforests widely separated by extremely hot and dry savannah. This paper reports novel phylogeographical analyses of the low-dispersing and forest-dependent Typoderus weevils in the Uluguru block of the EAM. One mitochondrial and two nuclear loci were used to infer phylogenetic relationships among 70 Typoderus specimens, 52 of them from 22 geographically diversified Uluguru litter sifting samples. Various analyses consistently detected 11 geographically coherent Typoderus clades, six of them formed by the Uluguru specimens, where five are taxonomically interpreted as species: T. admetus sp.n., T. furcatus, T. peleus sp.n., T. polyphemus sp.n. and T. subfurcatus. The sixth Uluguru clade temporary named Typoderus sp. 1808 and consistently recovered with the different genetic markers comprises specimens morphologically similar to, and likely conspecific with, those of T. admetus sp.n. If so, then within the confined area of Uluguru forest (40 x 6 km) T. admetus sp.n. displays (i) high genetic differentiation without morphological change and (ii) high morphological variation with very little molecular differences- the driving factors of this phenomenon remain unknown. Observed distribution of Typoderus is interpreted as simple vicariance of a widespread ancestor- no evidence suggests a founder-based dispersal. This study rejects two widely assumed hypotheses that low dispersal (= flightless) forest-dependent clades are represented in each EAM block by an endemic species and that each such species within a single EAM block is panmictic

First Alaocybites weevil (Insecta: Coleoptera: Curculionoidea) from the Eastern Palaearctic: a new microphthalmic species and generic relationships

The genus Alaocybites (Coleoptera: Curculionoidea), previously consisting of two eyeless Californian species, is for the fi rst time reported from the East Palaearctic Region. A new microphthalmic species, A. egorovi sp.n., is described from Primor-sky Kray, the Far East of Russia. An early Late Pliocene Alaskan weevil fossil previously attributed to the molytine genus Otibazo is assigned to Alaocybites and found almost undistinguishable from A. egorovi sp.n. Results of preliminary phylo-genetic analyses aimed to clarify phylogenetic affinities of Alaocybites are found controversial and inconclusive. The uncer-tainties of the contemporary classifi cation of orthocerous weevils are briefl y discussed. Alaocybites is provisionally retained in Raymondionymidae, with the absence of tarsomere IV on each leg being the family's most plausible apomorphy. Mono-phyly, geographical distribution and internal relationships of Raymondionymidae are briefl y discussed and compared with other predominantly Mediterranean groups of eyeless beetles. External and genital morphological characters of edaphic weevils with reduced eyes habitually resembling, or thought to be related to, Alaocybites are extensively illustrated

First Alaocybites weevil (Insecta: Coleoptera: Curculionoidea) from the Eastern Palaearctic: a new microphthalmic species and generic relationships

The genus Alaocybites (Coleoptera: Curculionoidea), previously consisting of two eyeless Californian species, is for the fi rst time reported from the East Palaearctic Region. A new microphthalmic species, A. egorovi sp.n., is described from Primor-sky Kray, the Far East of Russia. An early Late Pliocene Alaskan weevil fossil previously attributed to the molytine genus Otibazo is assigned to Alaocybites and found almost undistinguishable from A. egorovi sp.n. Results of preliminary phylo-genetic analyses aimed to clarify phylogenetic affinities of Alaocybites are found controversial and inconclusive. The uncer-tainties of the contemporary classifi cation of orthocerous weevils are briefl y discussed. Alaocybites is provisionally retained in Raymondionymidae, with the absence of tarsomere IV on each leg being the family's most plausible apomorphy. Mono-phyly, geographical distribution and internal relationships of Raymondionymidae are briefl y discussed and compared with other predominantly Mediterranean groups of eyeless beetles. External and genital morphological characters of edaphic weevils with reduced eyes habitually resembling, or thought to be related to, Alaocybites are extensively illustrated

Niphadomimus maia Grebennikov 2014, sp. n.

Niphadomimus maia sp. n. Figs. 5, 11E. Diagnostic description. Holotype, male (Figs. 5, 11E). Genbank accession: KJ427733. Length: 5.00 mm. Color black; prosternal depression delimited on each side by longitudinal keel; femoral tooth not higher than its width at base and weakly developed; elytral interstriae evenly and weakly tuberculate. Intraspecific variation. Length 5.00– 6.27 mm. Material examined. Holotype male (IZCAS): #2730, “P.R. CHINA, Yunnan, Cang Shan at Dali, N25°40'12" E100°06'10", 05.vii.2011, 3740m, sift37, V.Grebennikov ”. Paratypes (CNC, IZCAS, MTD): 8 exx, #2731–33 and 5 exx not numbered, same data as holotype. Distribution. Eastern slope on Cang Shan range above the city of Dali, Yunnan, China; sympatrically with N. electra sp. n. Elevation: 3740 m. Etymology. The species epithet is a Latinized Greek mythical name of Maia, eldest of the seven Pleiades, mother of Hermes by Zeus; noun in apposition.Published as part of Grebennikov, Vasily V., 2014, DNA barcode and phylogeography of six new high altitude wingless Niphadomimus (Coleoptera: Curculionidae: Molytinae) from Southwest China, pp. 151-173 in Zootaxa 3838 (2) on page 160, DOI: 10.11646/zootaxa.3838.2.1, http://zenodo.org/record/492179

Devernodes alkippe Grebennikov 2018, sp. n.

Devernodes alkippe sp. n. Figs 1A–G, 2A–G, 7A,B,G,H, 8A,B,G,H, 10, 11. Diagnostic description. Holotype male (Figs 1A–G, 7A,G, 8A,G), body length 3.2 mm, DNA barcode GenBank accession number in Fig. 10; unique combination of morphological characters in Table 3. Material examined. Holotype (currently in CNC, will be deposited in IZCAZ): “P. R. CHINA, Sichuan, Emei Shan, N 2933'56" E10321 '24", 26.v.2011, 1829m, sift06, V.Grebennikov”, “CNCCOLVG00002288”. Paratypes (CNC): 11 specimens, as in Fig. 10, same locality as holotype. Distribution. Known only from the type locality, Mount Emei in Sichuan, China (Fig. 12). Elevation: 1,463 – 1,850 m. Etymology. In Greek mythology the species epithet is a name of one of the seven sisters who, upon knowing that their father Alcyoneus has been killed by Heracles, threw themselves into the sea to be later transformed by Amphitrite, Poseidon's wife, into kingfisher birds (Alcedinidae); noun in apposition.Published as part of Grebennikov, Vasily V., 2018, Discovery of Lymantini weevils (Coleoptera: Curculionidae: Molytinae) outside the Americas: Devernodes, a new genus for five new species from Southeast Asia, pp. 363-380 in Zootaxa 4500 (3) on page 367, DOI: 10.11646/zootaxa.4500.3.4, http://zenodo.org/record/529769