Primocerus pijiguaense, 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 : 144-146

Primocerus pijiguaense sp. nov. Figs 12 E–H , 14G, H , 15A , 16B

Type material.

Holotype (♂): "VENEZUELA: Bolívar: 6°35.617'N, 66°49.238'W; 80 m; Los Pijiguaos; morichal/rock outcrop; 14.ix.2007; leg. A. Short, M. García, L. Joly; AS-07-015" (MIZA). Paratypes (14): VENEZUELA: Bolívar: same data as holotype (MALUZ, SEMC, 7, including DNA voucher specimen SLE 1029); same, except "6.viii.2008, AS-08-076" (SEMC, 1); same, except "at rock outcrop, seeps and streams at night, 9.vii.2010, leg. Short, Tellez, Arias, VZ10-0709-03A" (SEMC, 1); same, except "rock pools, 7.vii.2010, VZ10-0707-01A" (SEMC, 3, including DNA voucher specimen SLE 444); " 6°57.904'N, 66°36.392'W, 51 m, Outcrop ca. 15 Km NE. of los Pijiguaos, detritus flotation, 9.vii.2010, leg. Short & Tellez, VZ10-0709-01B" (SEMC, 1); " 7°29'47.3"N, 65°51'44.8"W, 45 m, 2 Km E. of Río Cuchivero, rock outcrop seeps, 6.viii.2008, leg. A. Short, M. García, L. Joly, AS-08-075" (SEMC, 1).

Differential diagnosis.

Primocerus pijiguaense can be differentiated by the presence of sharply impressed elytral punctures, with serial punctures not differentiated (e.g., they look similar to the ground punctures). It is very similar to P. maipure , from which it can be distinguished by the dorsal keel on the apical region of the median lobe and the widely rounded outer margins of the apical region of the parameres (Fig. 14G, H ; apical region of median lobe simple, non-keeled, and oblique and rather angulate outer margins of the apical region of the parameres in P. maipure , Fig. 14E, F ).

Description.

Body length 2.6-3.1 mm, width 0.9-1.7 mm. Body elongate oval, strongly convex (Fig. 12F ). General coloration dark brown. Elytra with ground punc tures sharply marked; serial punctures not differentiated (similar to ground punctation). Posterior elevation of mesoventrite with simple, very lowly raised curved transverse ridge. Metafemora with hydrofuge pubescence limited to anterodorsal surface. Apex of fifth abdominal ventrite rounded. Aedeagus (Fig. 14G, H ) with basal piece nearly 1.2 × longer than parameres; parameres nearly as long as median lobe, in lateral view with base perpendicular to longitudinal axis of aedeagus; outer margin of apical region of parameres widely rounded; apical region of median lobe with well-developed dorsal carina.

Etymology.

Named after Los Pijiguaos, the type locality for the species.

Distribution.

Primocerus pijiguaense has been collected at Los Pijiguaos and a few other localities north from it, at elevations between 45 and 80 m (Fig. 15A ).

Remarks.

All collections of this species were made either on small seepages over granite outcrops, or in small rock pools that had formed on the outcrops (e.g., Fig. 16B ).

Figures

Figure 12. Habitus of Primocerus spp.: A-D Primocerus maipure: A dorsal view B lateral view C ventral view D head, dorsal view. E-H Primocerus pijiguaense: E dorsal view F lateral view G ventral view H head, dorsal 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.

Figure 16. Habitat of Primocerus spp. A habitat and type locality for P. cuspidis, Venezuela, Tobogan de la Selva, collecting event AS- 08 - 080 b B habitat and type locality for P. pijiguaense, Venezuela, Los Pijiguaos, collecting event AS- 07 - 015 C habitat and type locality for P. neutrum, Venezuela, along La Escalera, collecting event AS- 08 - 058 D habitat and type locality for P. petilus, Brazil, Vale do Paraiso, collecting event BR 18 - 0203 - 01 G.