Hydraena shorti, Perkins, Philip D., 2011

Perkins, Philip D., 2011, New records and description of fifty-four new species of aquatic beetles in the genus Hydraena Kugelann from South America (Coleoptera: Hydraenidae), Zootaxa 3074, pp. 1-198 : 41-42

Hydraena shorti , new species

Figs. 68 (habitus), 72 (aedeagus), 189 (spermatheca), 201 (map)

Type Material. Holotype (male): Venezuela : Zulia, Perija National Park, Tukuko, Rio Manantial, gravel margin of stream, elev. 270 m, 9° 50.49' N, 72° 49.31' W, 29 i 2009, Short, Garcia, Camacho (VZ09-0129-01A). Deposited in the MIZA. Paratypes: Same data as holotype (34 SEMC).

Differential Diagnosis. A very finely sparsely punctate, strongly shining species with a very distinct piceous pronotal fascia; color band ratios ca. 6/10/6. Somewhat similar in dorsal habitus to H. venezuela ( Figs. 68 , 142 ); differentiated therefrom by the smaller size (ca. 1.25 vs. 1.38 mm), the narrower pronotal fascia (color band ratios ca. 6/10/6 vs. 5/15/5), the wider P2, and the narrower plaques. The aedeagus of H. shorti shows more resemblance to that of H. fasciola and H. mauriciogarciai , both of which have a completely testaceous pronotum ( Figs. 65–66, 72), than to H. venezuela ( Fig. 144). The females are unusual in having the apical margin of the last tergite serrate.

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.25/0.52; head 0.20/0.31; pronotum 0.30/0.40, PA 0.32, PB 0.38; elytra 0.74/0.52. Dorsum of head piceous; pronotum testaceous in front of and behind piceous fascia, ratios of color bands, as measured in midline, ca. 6/10/6; elytra dark brown; legs testaceous; maxillary palpi testaceous, tip not darker.

Frons punctures ca. 1xef, larger and denser near eyes than medially; interstices strongly shining, 1–2xpd laterally, 3–6xpd medially. Clypeus microreticulate laterally, very finely sparsely punctulate medially. Mentum and postmentum very sparsely very finely punctulate, shining. Genae raised, shining, without posterior ridge.

Pronotum weakly arcuate laterally; anterior margin straight behind eyes, emarginate behind frons, scintilla absent; very finely sparsely punctate, punctures ca. 1xpd of frons punctures, interstices strongly shining, 3–7xpd, punctures not appreciably larger and denser at anterior and posterior; PF1, PF2 and PF4 absent; PF3 shallow.

Elytra weakly arcuate laterally; rather convex, summit of posterior declivity slightly before midlength; lateral explanate margins narrow; on basal 1/3 punctures ca. 1xpd largest pronotal punctures, punctures becoming finer and more widely spaced toward posterior, obsolete behind posterior declivity. Intervals not raised, strongly shining, on basal 1/3 ca. 3–4xpd, as are interstices between punctures of a row, a few punctures subserial. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very shallow angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 4/1.5/5/4. P1 laminate; median carina sinuate in profile. P2 short, l/w ca. 3/4, sides parallel, apex raised slightly above mesoventral intercoxal process. Plaques moderately wide, straight, converging toward one another anteriorly, weakly raised, located at sides of deep median depression. Metaventrite with low anteromedian ridge and with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin slightly wider than P2. Protibia widened on medial margin to point at distal 2/3, emarginate between point and apex. Meso- and metatibia slender, straight. Male abdominal apex slightly asymmetrical; last tergite with apicomedian notch. Female (microslide mount, n=1): last tergite broadly rounded, free margin serrate, setae long, hair-like, not hooked; gonocoxite not midlongitudinally divided, apical margin sharply rounded, no transverse ridge evident at border of microreticulation; spermatheca type C2.

Etymology. Named in honor of the collector, Andrew Short.

Distribution. Currently known only from the type locality ( Fig. 201).

Figures

FIGURE 68. Hydraena shorti, holotype, dorsal and lateral habitus, and venter.

FIGURE 142. Hydraena venezuela, holotype, dorsal and lateral habitus, and venter.