Primocerus striatolatus, 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 : 146-147

Primocerus striatolatus sp. nov. Figs 13 D–F , 14K , 15B

Type material.

Holotype (♂): "SURINAME: Sipaliwini District/ 2°58'36.7782"N, 55°24'40.986"W; 400 m/ Camp 4 (high) Kasikasima; White Rock/ seepage area on trail; 24.iii.2012/ leg. A. Short; SR12-0324-01B" (NZCS). Paratypes (1): SURINAME: Sipaliwini District: Same data as holotype (SEMC, 1).

Differential diagnosis.

Primocerus striatolatus can be recognized by the presence of sharply impressed elytral punctures, with serial punctures well differentiated (larger and deeper than remainder punctures), longitudinally aligned to form elytral striae. It is similar to P. semipubescens , from which it can be differentiated by the hydrofuge pubescence of the metafemora covering basal 3/4 of the anterior surface (covering less than basal half in P. semipubescens ). It is also very similar to P. petilus , from which it can be differentiated by the elytral striae IX and X clearly impressed along their entire length (Fig. 13E ; elytral striae IX and X undefined along their basal fourth in P. petilus , Fig. 13B ).

Description.

Body length 3.1 mm, width 1.6 mm. Body elongate oval, strongly convex (Fig. 13D, E ). General coloration dark brown. Elytra with ground punctures sharply marked, and well-defined rows of serial punctures (forming elytral striae); elytral striae very slightly impressed along posterior half of elytra. Posterior elevation of mesoventrite with simple, curved, transverse ridge. Metafemora with hydrofuge pubescence covering basal 4/5 of anterior surface. Apex of fifth abdominal ventrite rounded. Aedeagus (Fig. 14K ) with basal piece nearly as long as parameres; parameres nearly as long as median lobe (median lobe inserted further into basal piece, thus appearing shorter than parameres); apex of parameres rounded; apex of median lobe rounded.

Etymology.

Named from the word stria, combined with the Latin word latus meaning broad, in reference to the comparatively broad shape of the body and the clearly defined elytral striae in this species.

Distribution.

Primocerus striatolatus has only been collected at one locality in the Kasikasima region in Suriname, at an elevation of 400 m (Fig. 15B ).

Remarks.

Collected on a forested seepage that had lots of detritus.

Figures

Figure 13. Habitus of Primocerus spp.: A-C Primocerus petilus: A dorsal view B lateral view C ventral view. D-F Primocerus striatolatus: D dorsal view E lateral view F ventral view. G-I Primocerus semipubescens: G dorsal view H lateral view I ventral view. Scale bars: 1 mm.

Figure 14. Thorax, abdomen and aedeagus of Primocerus spp.: A-D Primocerus neutrum: A ventral view of mesoventrite (white arrow pointing transverse ridge) B posterior view of metafurca C fifth abdominal ventrite D aedeagus. E-L aedeagus: E, F Primocerus maipure: E dorsal view F lateral view. G, H Primocerus pijiguaense: G dorsal view H lateral view I Primocerus gigas J Primocerus petilus K Primocerus striatolatus L Primocerus cuspidis. Scale bars: 0.25 mm.

Figure 15. Distribution of Primocerus spp.