Deltepilissus Pereira 1949
Creators: name: Silva, Fernando A. B.
name: Ferreira, Ana B. M.
name: Génier, François
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Deltepilissus

description: Deltepilissus Pereira, 1949
Deltepilissus Pereira 1949: 231 (original description); Pereira & Martínez 1956: 96, 125, 184 (identification key, catalog); Halffter 1961: 231 (identification key); Vulcano & Pereira 1964: 660 (catalog); Halffter & Matthews 1966: 261 (distribution); Halffter & Martínez 1977: 37, 52, 66 (identification key, taxonomic remarks, checklist); Halffter & Edmonds 1982: 139 (distribution); Vaz-de-Mello 2000: 186, 192 (checklist); Krajcik 2006: 47 (checklist); Vaz-de-Mello et al. 2011: 5, 10, 18, 25, 32, 40, 55 (identification key); Krajcik 2012: 88 (checklist); Tarasov & Dimitrov 2016: 15 (new delimitation for Deltochilini); Cupello & Vaz-de-Mello 2018: 18 (taxonomic remarks); Schoolmeesters 2020 (catalog); Vaz-de-Mello 2021 (checklist).
Type species. Deltepilissus travassosi Pereira, 1949 by original designation (currently a junior subjective synonym of Canthon infernalis Harold, 1880).
Diagnosis. Among the genera included in the tribe Deltochilini (sensu Tarasov & Dimitrov 2016), Deltepilissus can be distinguished by reduced tarsal claws (Figs 1G–I, 2I–L); protibiae long, weakly widened apically, with three small and spaced, lateral teeth (Figs 1A–B, 2A–D); metatibial spur short, widened apically, with spiniform process at least on internal edge (Figs 1H–I, 2K–L).
Redescription. Colour and tegument sculpture (Figs 1A–B, 2A–D). Head, pronotum, elytra and ventral surface with black, copper or red coloration. Body densely punctate. Length. 9–15 mm. Head (Figs 1C, 2E). Surface with strong, deep and dense punctures. Clypeus with two widely spaced, small teeth. Eye comma shaped in dorsal view. Dorsal interocular space at least 10 times eye width. Lateral margin of head regularly curved outward. Thorax (Figs 1A, 2A, 2C). Pronotum convex; anterior angles acute, directed forward. Lateral edge of pronotum regularly curved outward; posterior angle obtuse. Pronotum with a longitudinal sulcus on midline posteriorly. Hypomera not excavated (Figs 1D, 2F). Mesometasternal suture slightly arched. Metaventrite punctures variable in size; smaller and denser medially (Figs 1B, 2B, 2D). Elytra (Figs 1A, 2A, 2C). Lateral margin slightly curved outward. Elytral striae visibly impressed. Pseudepipleural carina complete, visible on entire length of epipleuron. Elytral lateral edge formed by the pseudepipleural carina. Interstriae flattened, without carinae or tubercles basally and apically. Abdomen (Figs 1E, 2B, 2D, 2G). Punctures denser on lateral surface of ventrites. Sixth ventrite longer than 2nd, 3rd, 4th and 5th. Pygidium rounded apically, densely punctate, separated from propygidium by carina (Figs 1F, 2H). Legs. Femora densely punctate (Figs 1B, 2B, 2D); anterior and posterior edges marginate. Protibiae long, thin and curved. Apical one-quarter of protibiae abruptly expanded along inner edge (Figs 1A–B, 2A–D). Apical one-third of protibiae with three distinct lateral teeth; medial lateral tooth closer to apical tooth than to basal tooth (Figs 1A–B, 2A–D). Meso- and metatibiae smoothly arched toward body, not abruptly expanded along inner edge (Figs 1A–B, 2A–D). Longitudinal carinae of meso- and metatibiae with row of setae. Metatibial spur short, sinuous and spatulate; bifurcate apically (Figs 1I, 2L), almost rounded (Fig. 1H), or with a conspicuous denticle (spiniform process) on inner edge (Fig. 2K). First meso- and metatarsomeres triangular; tarsomeres 2–4 trapezoidal, the last subrectangular (Figs 1H–I, 2K–L). Tarsal claws reduced (Figs 1G–I, 2I–L). Secondary sexual characters. Females can be distinguished from males, in general, by the last abdominal ventrite evenly wide (Fig. 2D); in males, the last abdominal ventrite is subtly narrower medially (Figs 1E, 2G). Females have the protibial spur bifurcate apically (Fig. 2J); in males, protibial spur is wide and rounded, lacking denticle apically (Fig. 1G), or with a denticle on external edge (Fig. 2I). Females have also sinuous and bifurcate apex of metatibial spur, with denticle (spiniform process) on internal and external edges (Figs 1I, 2L); in males, metatibial spur only have denticle on inner edge (Fig. 2K), or it is rounded apically, with inner denticle almost inconspicuous (Fig. 1H). Furthermore, females have the apical third of metatibiae almost straight (Figs 1I, 2L), whereas in males the apical third of metatibiae is distinctly curved inward (Figs 1H, 2K). Tegmen. Parameres symmetrical, subtriangular in lateral view (Figs 3C, 3F), pointed and curved inward apically (Figs 3A–F). Endophallus. Lamella copulatrix absent. Superior right peripheral endophallite circular, with curved handle-shaped extension and ring with thin border (Figs 3G–H). Frontolateral peripheral endophallite with irregular shape (Figs 3I–J). Complex of axial and subaxial endophallites elongate, with irregular shape (Figs 3M–N). There are also two short additional endophallites (Figs 3K–L) between the frontolateral peripheral endophallite and the axial and subaxial endophallites.
Remarks. Although none of the specimens with collecting data provide indications on the natural history of the genus, we suspect that species of Deltepilissus are inquilines. We base this assumption on the fact that none specimen was collected in dung traps or any other type of baited pitfall traps. The reduced tarsal claws is a common adaptation for inquiline, however no other obvious adaptations are present such as concealed mouthparts, highly modified legs or trichome. The rather dense, small swallow punctures with a minute seta present in Deltepilissus are eerly similar to those found in Ateuchus (Lobidion) punctatissimus (Génier, 2010), a documented ant inquiline species (Génier, 2010). Another possibility, considering its fully functional wings and rather elongate legs, would be a predatory behavior on social insects. Meliponine bees are common in the Atlantic rainforest and nests in trees. Flying higher in the canopy would explain the fact that species of Deltepilissus have also never been collected in flight interception traps set on the ground. This is purely speculative at the moment, but it would be interesting to verify these hypotheses.
description: Published as part of Silva, Fernando A. B., Ferreira, Ana B. M. & Génier, François, 2022, Taxonomic revision of the genus Deltepilissus Pereira, 1949 (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilini), pp. 83-96 in Zootaxa 5120 (1) on pages 85-86, DOI: 10.11646/zootaxa.5120.1.5, http://zenodo.org/record/6388909