Ephydrolithus hamadae, Girón & Short, 2019

Giron, Jennifer C. & Short, Andrew Edward Z., 2019, Three additional new genera of acidocerine water scavenger beetles from the Guiana and Brazilian Shield regions of South America (Coleoptera, Hydrophilidae, Acidocerinae), ZooKeys 855, pp. 109-154 : 126-127

Ephydrolithus hamadae sp. nov. Figs 5 A–D , 7 A–D , 8 , 9C

Type material.

Holotype (♂): "BRAZIL: Minas Gerais: Lassance; 17.83384S, 44.50515W; 568 m; Cachoeira da Palmeira; flotation of root mats and moss from side of waterfall & seepage; 2.iii.2018; leg. Benetti & team; BR18-0302-04A" (INPA). Paratypes (7): BRAZIL: Minas Gerais: Same data as holotype (INPA, SEMC, 7 including DNA voucher SLE 1506).

Differential diagnosis.

Ephydrolithus hamadae is very similar to E. teli . Both species can only be distinguished from each other by characteristics of the aedeagus.

Description.

Body length 2.6-3.2 mm, width 1.5-1.7 mm. Body elongate oval, moderately convex (Fig. 5B ). General coloration yellowish to dark brown, slightly paler along margins of pronotum and elytra. 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 2/3; metafemora with hydrofuge pubescence on tibial grooves. Apex of fifth abdominal ventrite truncate (Fig. 7C ). Aedeagus (Fig. 7D ) with basal piece 0.6 × the length of parameres; parameres nearly 0.5 × greatest width of median lobe, with outer margins slightly sinuate; apex of parameres rounded, obliquely directed; apex of median lobe “pinched”, narrowly rounded.

Etymology.

Named after Neusa Hamada from the Instituto Nacional de Pesquisas da Amazônia, Manaus (INPA), in recognition of her support on recent expeditions collecting aquatic beetles in Brazil.

Distribution.

Known only from the type locality (Fig. 8 ).

Remarks.

This species was collected by gathering moss and roots from bottom and margin of a seepage that was next to a large waterfall (Fig. 9C ). Specimens were collected by placing the moss and roots in a pan with water, where they floated to the surface along with one specimen of E. spiculatus .

Figures

Figure 5. Habitus of Ephydrolithus spp.: A-D Ephydrolithus hamadae: A dorsal view B lateral view C ventral view D head, dorsal view. E-H Ephydrolithus teli: E dorsal view F lateral view G ventral view H head, dorsal view. Scale bars: 1 mm.

Figure 7. Thorax, abdomen and genitalia of Ephydrolithus spp.: A-D Ephydrolithus hamadae: A ventral view of mesoventrite (white arrow pointing transverse ridge) B posterior view of metafurca C fifth abdominal ventrite D aedeagus E aedeagus of Ephydrolithus teli. F, G Ephydrolithus spiculatus: F aedeagus G oblique view of mesoventrite (black arrow pointing well-developed tooth) H aedeagus of Ephydrolithus ogmos I aedeagus of Ephydrolithus minor. Scale bars: 0.25 mm.

Figure 8. Distribution of Ephydrolithus spp.

Figure 9. Habitat of Ephydrolithus spp. A, B habitat and type locality for E. minor and E. ogmos, Brazil, Pico do Barbado, collecting event BR 18 - 0226 - 01 C C habitat and type locality for E. hamadae and E. spiculatus, Brazil, Cachoeira da Palmeira, collecting event BR 18 - 0302 - 04 A D habitat and type locality for E. teli, Brazil, Pico do Barbado, collecting event BR 18 - 0226 - 01 B.