AnimaliaColeopteraHydrophilidaeGirónJennifer C.ShortAndrew Edward Z.Three additional new genera of acidocerine water scavenger beetles from the Guiana and Brazilian Shield regions of South America (Coleoptera, Hydrophilidae, Acidocerinae)Zookeys136201985510915410.3897/zookeys.855.33013 Ephydrolithus minor http://zoobank.org/E49E34BB-6106-451D-A670-0ACF02FBB604 sp. nov.Figs 6E–H, 7I, 8, 9A, BType material.

Holotype (♂): “BRAZIL: Bahia: Abaíra; 13.29053S, 41.90489W; 1705 m; Pico do Barbado W of Catolés; vertical seep on rock; 26.ii.2018; leg. Benetti & team; BR18-0226-01C” (INPA). Paratypes (15): BRAZIL: Bahia: Same data as holotype (SEMC, 8 including DNA vouchers SLE-1511, SLE-1512; INPA, 7).

Differential diagnosis.

Ephydrolithusminor is easily recognized among its congeners by its small size.

Description.

Body length 1.8–2.2 mm, width 0.9–1.3 mm. Body elongate oval, strongly convex (Fig. 6F). General coloration dark brown, slightly paler along margins of pronotum. Posterior elevation of mesoventrite with well-defined, curved transverse ridge. Elytra without striae or serial punctures. Pro- and mesofemora covered with hydrofuge pubescence along basal half; metafemora with glabrous tibial grooves. Apex of fifth abdominal ventrite rounded. Aedeagus (Fig. 7I) with basal piece 0.45 × the length of parameres; greatest width of parameres similar to greatest width of median lobe, with outer margins evenly convex; apex of parameres truncate, obliquely directed; apex of median lobe rather widely rounded.

Etymology.

Named with the Latin word minor meaning small, in reference to the species being the smallest member of the genus.

Distribution.

Only known from the type locality, Pico do Barbado (Fig. 8).

Remarks.

The type series was collected on a high-elevation seepage over a vertical cliff. The rock face had moss and algal growth on same areas (Fig. 9A, B).

Habitus of Ephydrolithus spp.: A–DEphydrolithusogmos: A dorsal view B lateral view C ventral view D head, dorsal view. E–HEphydrolithusminor: E dorsal view F lateral view G ventral view H head, dorsal view. Scale bars: 1 mm.

Thorax, abdomen and genitalia of Ephydrolithus spp.: A–DEphydrolithushamadae: A ventral view of mesoventrite (white arrow pointing transverse ridge) B posterior view of metafurca C fifth abdominal ventrite D aedeagus E aedeagus of Ephydrolithusteli. F, GEphydrolithusspiculatus: F aedeagus G oblique view of mesoventrite (black arrow pointing well-developed tooth) H aedeagus of EphydrolithusogmosI aedeagus of Ephydrolithusminor. Scale bars: 0.25 mm.

Distribution of Ephydrolithus spp.

Habitat of Ephydrolithus spp. A, B habitat and type locality for E.minor and E.ogmos, Brazil, Pico do Barbado, collecting event BR18-0226-01C C habitat and type locality for E.hamadae and E.spiculatus, Brazil, Cachoeira da Palmeira, collecting event BR18-0302-04A D habitat and type locality for E. teli, Brazil, Pico do Barbado, collecting event BR18-0226-01B.