Primocerus maipure, 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 : 142

Primocerus maipure sp. nov. Figs 12 A–D , 14E, F , 15A

Type material.

Holotype (♂): "VENEZUELA: Amazonas: 5°30.623'N, 67°36.109'W; 100 m; ca. 15 Km S. of Puerto Ayacucho; rock pools on top; 14.ix.2007; leg. A. Short; AS-07-011b" (MIZA). Paratypes (10): VENEZUELA: Amazonas: 5°23.207'N, 67°36.922'W; 125 m/ Tobogán de la selva, old “Tobogancito” / upstream at small slide; 12.ix.2007/ leg. M. García; AS-07-007b (SEMC, 1); " 5°30.518'N, 67°36.079'W; 100 m/ ca. 15 Km S. of Puerto Ayacucho; isolated seepage/ 13.ix.2007; leg. A. Short; AS-07-009a" (SEMC, 1); same data as holotype (SEMC, 2, including DNA voucher specimen SLE 1034); same except "pools at outcrop base, AS-07-011x" (SEMC, 2); "110 m; rock outcrop pools; 8.ix.2007; leg. A. Short, M. García; AS-08-081b" (SEMC, 1); 5°48.414'N, 67°26.313'W; 80 m/ nr. Iboruwa, “Tobogancito” / 7.viii.2008; leg. A. Short, M. García, L. Joly/ AS-08-078" (SEMC, 3).

Differential diagnosis.

Primocerus maipure can be differentiated by the presence of sharply impressed elytral punctures, with serial punctures only slightly differentiated, longitudinally aligned (more evidently so along posterior half of elytra, Fig. 12A, B ). It is very similar to P. pijiguaense , from which it can be distinguished by its simple median lobe and the oblique and rather angulate outer margins of the apical region of the parameres (Fig. 14E, F ; apical region of median lobe dorsally keeled along apical region, and widely rounded outer margins of the apical region of the parameres in P. pijiguaense , Fig. 14G, H ).

Description.

Body length 2.6 mm, width 1.5 mm. Body elongate oval, strongly convex (Fig. 12A, B ). General coloration brown. Elytra with ground punctures sharply marked, with serial punctures only slightly differentiated, longitudinally aligned, more evidently so along posterior half of elytra (Fig. 12A, B ). 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 truncate. Aedeagus (Fig. 14E, F ) with basal piece nearly 1.2 × longer than parameres; parameres nearly as long as median lobe, in lateral view with base oblique to longitudinal axis of aedeagus; outer margin of apical region of parameres oblique and rather angulate; apical region of median lobe simple, non-carinate.

Etymology.

Noun in apposition. Named after the Maipure, one of the pre-Columbian indigenous tribes that inhabited the "Spanish Guyana" region, and the language they spoke.

Distribution.

Primocerus maipure has been collected at localities south of Puerto Ayacucho in the Venezuelan Amazon, at elevations between 80 and 125 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.

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.