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

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

Devernodes asteria Grebennikov 2018, sp. n.

Devernodes asteria sp. n. Figs 3A–G, 7C,I, 8C,I, 9C, 10, 11. Diagnostic description. Holotype male (Figs 3A–G, 7C,I, 8C,I, 9C), body length 3.2 mm, DNA barcode GenBank accession number in Fig. 10; unique combination of morphological characters in Table 3. Material examined. Holotype (CNC): “ VIETNAM, Tam Dao, N 2127'54" E10538 '44", 12.v.2012, 1218m, sift02, V.Grebennikov”, “CNCCOLVG00004340”. Paratypes (CNC): 4 specimens, as in Fig. 10, same locality as holotype. Distribution. Known only from the type locality, the Tam Dao Mountains in northern Vietnam (Fig. 12). Elevation: 1,219 –1,240 m. Etymology. One of the seven daughters of Alcyoneus; 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 368, DOI: 10.11646/zootaxa.4500.3.4, http://zenodo.org/record/529769

Niphadomimus celaeno Grebennikov 2014, sp. n.

Niphadomimus celaeno sp. n. Figs. 3, 11C. Diagnostic description. Holotype, male (Figs. 3, 11C). Genbank accession: KJ427748. Length: 4.17 mm. Color dark reddish; prosternal depression delimited on each side by longitudinal keel; femoral tooth not higher than its width at base and moderately developed; elytral interstriae evenly and pronouncedly tuberculate. Material examined. Holotype male (IZCAS): #2476, “P.R. CHINA, Sichuan, NE slope Gongga Shan, N29°52'10" E102°02'01", 12.vi.2011, 3620m, sift16, V.Grebennikov ”. Distribution. Gongga Shan region in Sichuan, China; sympatrically with N. alcyone sp. n. Elevation: 3620 m. . Etymology. The species epithet is a Latinized Greek mythical name of Celaeno, one of the Pleiades, mother of Lycus and Eurypylus by Poseidon; 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 pages 157-158, DOI: 10.11646/zootaxa.3838.2.1, http://zenodo.org/record/492179

Phylogenetic placement of a new Melanophilharmostes Paulian, 1968 pill scarab (Coleoptera: Hybosoridae: Ceratocanthinae) from Cameroon: molecular results decipher misleading morphology

Grebennikov, Vasily V. (2022): Phylogenetic placement of a new Melanophilharmostes Paulian, 1968 pill scarab (Coleoptera: Hybosoridae: Ceratocanthinae) from Cameroon: molecular results decipher misleading morphology. Zootaxa 5087 (3): 441-450, DOI: https://doi.org/10.11646/zootaxa.5087.3.

Oreoscotus affinis Grebennikov 2018, comb. n.

<i>Oreoscotus affinis</i> (Hustache, 1936) comb. n. (Figs. 2A, B) <p> <i>Molytophilus affinis</i> Hustache, 1936: 492 (description)</p> <p> <b>Type locality:</b> Abyssinie: entre Djem-Djem et Wouramboulchi, vers 9000 pieds.</p> <p> <b>Type specimens: Primary:</b> Holotype (by monotypy, Figs. 2A, B), unsexed (NHMUK): “ Type [p] \ TYPE [h] \ Abyssinia: Between Djem-Djem and Wouramboulchi. 8,000–9,000ft. 30.ix–1.x.1926. J.Omer Cooper. [p] \ Specimen figured [h] \ <i>Molytophilus affinis</i> [h] Hustache det. [p]”.</p> <p> <b>Remarks.</b> The only known specimen of this nominal species was collected on the watershed separating the Blue Nile basin and that of Awash River (spelt as “Hawash” in Omer-Cooper [1930], map 2) some 75 km W of Addis-Ababa and at relatively high altitude of about 2438–2743 meters.</p>Published as part of <i>Grebennikov, Vasily V., 2018, Both non-type species of Molytophilus (Coleoptera: Curculionidae: Molytinae) are transferred to Oreoscotus, pp. 393-396 in Zootaxa 4418 (4)</i> on page 395, DOI: 10.11646/zootaxa.4418.4.6, <a href="http://zenodo.org/record/1244950">http://zenodo.org/record/1244950</a&gt

Devernodes Grebennikov 2018, gen. n.

Devernodes gen. n. Type species: Devernodes chthonia sp. n., here designated. Diagnosis. Adults of the genus Devernodes can be most efficiently distinguished from those of other Curculionidae distributed in the Palaeaerctic or Oriental Regions by a unique combination of two easy-to-see head characters: antennae with 6-segmented funicle and apparently unsegmented club, as well as a strong constriction separating the eye-bearing rostrum from the head capsule. Life stages of Devernodes other than adults are unknown and cannot be identified using data other than the herein released DNA sequences. Description. Black or dark-brown, with compact and strongly sclerotized body, about 3–5 mm in body length, in dorsal view elongate, parallel-sided or slightly rounded. Rostrum variously curved, about 4 times as long as wide, with longitudinal lines of punctures sometimes merging in grooves. Prementum distinctly visible in ventral view. Antennae with apparently unsegmented club and funicle consisting of six antennomeres. Eyes fully developed and rounded or partly reduced and crescentic, each consisting of about 7–30 ommatidia. Head capsule spherical, smooth and shiny, without punctures or pilosity, separated from eye-bearing rostrum by notable constriction. Pronotum densely and evenly punctate, prothorax without ocular lobes, procoxae contiguous or narrowly separated, all femora without spurs or spines. Elytral shoulders effaced, each elytron with 7 or 9 punctate striae and with short, sparse setae on intrestriae. Pygidium in both sexes formed by tergite VII. Male sternite IX Ishaped (=not Y-shaped), male genitalia of pedal type, without large internal sclerotization. Each of two female hemisternites IX entire (not subdivided into apical “stylus” and basal “coxite”). Diversity, distribution and biology. Biological information on all five Devernodes species is restricted to the collecting circumstances suggesting that the adult beetles inhabit forest floor litter in Southeast Asia. It should be noted that despite intense sampling in China and Taiwan (Grebennikov 2018b), Mount Emei Shan is the only locality where specimens of Devernodes were recorded. Etymology. Devernodes, patronymic, derived by adding the Latin suffix -odes to the family name of Linda DeVerno (retired, formerly Director of the Ottawa Plant Laboratory, Canadian Food Inspection Agency, Ottawa, Canada), in recognition of her role in development of the sampling program in the Asia-Pacific Region, which lead to the discovery of this new genus. Gender masculine.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 365, DOI: 10.11646/zootaxa.4500.3.4, http://zenodo.org/record/529769

Tazarcus aeaea Grebennikov 2020, sp. n.

<i>Tazarcus aeaea</i> sp. n. <p>Figs 1, 4, 5</p> <p>http://zoobank.org/ urn:lsid:zoobank.org:act: 3EA886A2-BA5C-4F0A-AA07-49558CD9A936</p> <p> <b>Type locality.</b> Tanzania, West Usambara Mts., Mkusu Forest, S4.76585° E38.36022°, 1576 m.</p> <p> <b>Description.</b> Length of pronotum and elytra in dorsal view 2.0– 2.5 mm (n=7); lateral body contour in dorsal view not constricted between pronotum and elytra; lateral sides of posterior half of pronotum and elytra at middle evenly curved; disc of pronotum completely covered by dense whitish pilosity; procoxae separated by distance greater than half their length; elytral punctures on striae small, their diameter not greater than 0.2 of width of interstriae; elytral interstriae with row of prominent appressed scales as long as width of interstriae; male genitalia: Figs 5 E–F; DNA: Table 2.</p> <p> <b>Geographic variability.</b> Adults of the new species from South Pare and West Usambara populations appear morphologically indistinguishable, even though genetically distinct (Fig. 4).</p> <p> <b>Material examined.</b> Holotype (CNC), male, “ TANZANIA, W. Usambara Mts., Mkusu For., S4.76585° E38.36022°, 1576m, 14.i.2013, sift47, V.Grebennikov”, “CNCCOLVG00005480”. Paratypes (CNC), 3: same data as holotype, specimens 5479, 9337, 9338. Additional material: 4 (CNC): in ethanol, same data as holotype; 1 (in collection of D. McKenna): same data as holotype; 1 (CNC): “ TANZANIA, South Pare Mts., Chome For., S4.26865° E37.92944°, 2318m, 3.i.2013, sift36, V.Grebennikov”, 2 (CNC): “ TANZANIA, South Pare Mts., Chome For., S4.26945° E37.92814°, 2239m, 3.i.2013, sift37, V.Grebennikov”.</p> <p> <b>Distribution.</b> This species is known from two nearby EAM localities in Tanzania, South Pare and West Usambara.</p> <p> <b>Etymology.</b> The species epithet is a Latinized Greek mythical name of Aeaea, an island of the goddess Circe, who is known for transforming her offenders into animals, and it is a noun in apposition.</p>Published as part of <i>Grebennikov, Vasily V., 2020, Tazarcus, a new phylogenetically unplaced genus of two flightless weevils with metapleural ridge from the Eastern Arc Mountains, Tanzania (Coleoptera: Curculionidae: Molytinae), pp. 421-434 in Zootaxa 4766 (3)</i> on page 426, DOI: 10.11646/zootaxa.4766.3.2, <a href="http://zenodo.org/record/3765549">http://zenodo.org/record/3765549</a&gt

Phylogeography and sister group of Lupangus, a new genus for three new flightless allopatric forest litter weevils endemic to the Eastern Arc Mountains, Tanzania (Coleoptera: Curculionidae, Molytinae)

This paper reports discovery of a new genus Lupangus gen. n. with three new flightless weevils endemic to the forests of the Eastern Arc Mountains in Tanzania: L. asterius sp. n. (East Usambara; the type species), L. jason sp. n. (Uluguru) and L. orpheus sp. n. (Udzungwa). Maximum Likelihood phylogenetic analyses using parts of mitochondrial (COI), nuclear ribosomal (28S) genes, as well as the nuclear spacer region (ITS2) from 46 terminals grouped together the reciprocally monophyletic Lupangus (3 terminals) and Typoderus (3 terminals), with all three clades strongly supported. Phylogenetic analysis of 32 COI-5’ sequences recovered Lupangus species as reciprocally monophyletic, with L. orpheus being the sister to the rest. Internal phylogeny within both L. jason and L. orpheus are geographically structured, while that of L. asterius is not. Temporal analysis of Lupangus evolution using COI-5’ data assessed under slow and fast substitution rate schemes estimated separation of mitochondrial lineages leading to three Lupangus species at about 7–8 Ma and about 1.9–2.1 Ma, respectively. Temporal analyses consistently failed to suggest correlation between the timing of Lupangus evolution and the late Pleistocene climatic fluctuations, thus rejecting the hypothesis of faunal interchanges during the wettest periods of the last million years. Applicability of flightless weevils for dispersal-vicariance analysis is reviewed, and their mostly undocumented and taxonomically entangled diversity in the Tanzanian Eastern Arc Mountains is briefly highlighted