New species and new distributional records of the hygropetric water scavenger beetle genus Oocyclus Sharp (Coleoptera, Hydrophilidae) from the Brazilian Shield Author Alencar, Janderson Batista R. Author Short, Andrew Edward Z. Author Hamada, Neusa text Zootaxa 2022 2022-01-06 5087 2 275 305 journal article 2761 10.11646/zootaxa.5087.2.3 edccb027-e609-497d-8cd3-d4d2910cabde 1175-5326 5824101 B5807029-3C66-4592-A224-647A3BFD6BB5 Oocyclus ecolab sp. n. ( Figs. 2a–e , 11a , 14 ) Type material. Holotype (male) : “ BRASIL : MINAS GERAIS , Itabirito , Córrego prox. a Fazenda Velha , long - 43.8091, lat -20.2991, 862 m a.s.l. ,rock-face seepages 20.vi.2019 , leg. J.B. R .Alencar” ( INPA , Coleoptera , in alcohol). Diagnosis . Medium-sized species. Pronotum with rounded posterolateral margins. Elytra surface even, with rows of fine systematic punctures bearing short setae, interrupted in some regions along their length; lateral rows very indistinct, blending with surrounding ground punctation. Elytral sutural interval not raised. Prosternum with two anteromedial spine-like setae. Abdominal ventrites dark brown, not paler than thoracic ventrites, in strong contrast to yellow to light brown legs and pseudoepipleura. Adult . Body length 4.2 mm (n= 1); TL/GW 1.76 mm . General body shape broadly oval, slightly convex. Color . Dorsum black ( Fig. 2a ), covered with dense, irregular green or bronze sheen. Anterolateral margins of pronotum with pale strip, extending ca. 4/5 along lateral margin. Elytra with irregular patches of bronze or green iridescence; with row of rounded black [=without sheen] spots along suture. Each elytron with two small circular pale spots: anterior pale spot on distal third, about twice as far from suture than posterior spot; posterior spot situated on distal quarter. Maxillary and labial palps yellow. Ventral face of head dark brown to black. Lateral margins of prosternum yellowish brown; pseudoepipleura and epipleura yellowish brown. Thorax dark brown to black ventrally. Legs light brown to yellow, except for dark brown coxae and base of femora. Abdominal ventrites dark brown, with slightly lighter posterior margins on ventrites 1–4, sometimes with pale patches laterally on ventrites 2–3. Head . Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width of one puncture ( Fig. 2d ). Ground punctation on labrum denser than on clypeus, distance between punctures 0.5– 1.5× width of one puncture; with few distinct systematic punctures medially. Labrum bearing short setae. Clypeus with several scattered indistinct systematic punctures laterally; bearing short setae. Frons with irregular row of systematic punctures toward the median plane of each eye and few fine setae around ocular suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical segment longer than penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth, with scattered coarse punctures; subquadrate, anterior margin slightly convex and depressed. Thorax . Ground punctation on pronotum and elytra evenly distributed and moderately coarse ( Figs. 2a, c, d ). Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and posterior series each forming irregular field. Lateral margins of pronotum with fine setae distributed along its length, being more densely pubescent in anterior half. Pronotal posterolateral angles rounded. Sutural interval on elytra not raised. Elytral interval with weak or non-existent pubescence in ground punctation (e.g. Figs. 12a, c, d ). Elytra with five rows of systematic punctures: rows 1 and 2 each represented by punctures not larger that surrounding punctuation and at about same spacing; rows 3–5 with punctures not larger than surrounding ground punctuation and as such hardly distinguishable. Elytral surface without any depression. Humeral region (in frontal view) without antero-medial elevation. Elytral margins with short spine-like setae equally spaced along its length. Prosternum with clearly defined median carina; slightly elevated anteromedially ( Fig. 2e ); elevated region with two spine-like setae. Elevated process of mesoventrite wide and elongate, about twice as long as wide; slightly raised anteriorly; with 3–4 coarse spine-like setae. Metaventrite with oval glabrous area posteromedially, slightly longer than wide; length of glabrous area about two-thirds length of metaventrite. Procoxae with fine short pubescence and set with coarse, short spine-like setae; grouped on basal half. Protibiae each with 6–7 spine-like setae on dorsal face. Meso- and metafemora with scattered punctures bearing short thickened, spine-like setae. Abdomen . Ventrites covered with setae of varying lengths; ventrites 1–4 with scattered, long setae, distinctly longer than longest setae on metaventrite, ventrite 5 more densely pubescent ( Fig. 2b ). Aedeagus: outer margin of parameres weakly sinuous, gradually tapering to apex, curving inward; inner margin, sinuous, gradually tapering towards apex (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore located at fourfifths length of median lobe. Basal piece rounded ( Fig. 11a ). Etymology . The specific epithet ecolab is derived from the acronym of the Community Ecology Lab of the Universidade Federal do Amazonas , in Brazil . It is a tribute to all the support received for the development of this work. To be treated as a noun in apposition. Distribution . Brazil ( Minas Gerais ) ( Fig. 14 ). Remarks. This species shares several diagnostic features with O. caparao Clarkson & Short, 2012 : non-pale abdominal ventrites, elytral suture not raised, elytra surface with rows of systematic punctures bearing short setae. However, O. caparao differs in that its elytral surface has faint, very shallowly impressed longitudinal grooves near the suture and the prosternum usually set with six spine-like setae, while longitudinal grooves are absent and the prosternum bears two spine-like setae in O. ecolab sp. n.