Berosus corozo Oliva & Short

Oliva, Adriana & Short, Andrew E. Z., 2012, Review of the Berosus Leach of Venezuela (Coleoptera, Hydrophilidae, Berosini) with description of fourteen new species, ZooKeys 206, pp. 1-69 : 19-21

Berosus corozo Oliva & Short sp. n. Figs 14A, 15C

Type material.

Holotype (male): "VENEZUELA: Guarico/ Corozo Pando (8kmN.)/ 17 20-21 June 1984/ blacklight/ F.W. Eiland & V. Linares", "HOLOTYPE/ BEROSUS/ corozo sp. n./ des. Oliva & Short" (MIZA). Paratypes (31): VENEZUELA: Apure State: Hato El Frio, Fundo Ceibote, 20.v.1975, leg. C. R osales (21 exs., MIZA, SEMC, NHMW, NMPC); Fundo La Florida, Rio Quitaparo, 7°05'N, 68°26'W, 42 m, 11-14.vi.1999, leg. E. Osuna & A. Chacon (1 ex., MIZA). Guárico State: Same data as type (4 exs., USNM, SEMC); same data but 17-18.vi.1984 (5 exs., USNM, MALUZ).

Diagnosis.

Moderate-sized species of the Berosus holdhausi complex, without metallic luster on dorsum, resembling Berosus marquardti Knisch, but without reddish hue on dorsum, with mesoventral process laminar, anterior tooth of this process straight, carina on first ventrite straight in lateral aspect and with median lobe of male genitalia subapically angular, apically narrow. This species is remarkable by the convex, short, broad body shape and the very coarse dorsal sculpture (Fig. 14A).

Description.

Body length: 3.6-4.3 mm. (holotype: total length: 4.3 mm; humeral width: 1.55 mm). Shape convex. Dorsum entirely testaceous, yellow in the type specimens, with base of frons, paramedial bands on pronotal disc and scutellum slightly darker. Elytra with small, weak darker spots on elytral disc and apical portion; the usual humeral and lateral spots are absent.

Pronotal punctures 3-6 times as large as ommatidia. Punctures on inner elytral striae about twice as large as pronotal ones, those on outer striae gradually larger. Inner interstriae about the width of striae, step-shaped, flat, shining, sparsely but deeply punctate. Outer interstriae 9 and 10 narrower than striae, weakly convex; interstria 11 weakly costate.

Mesoventral process in the shape of a short, strongly raised lamina with two teeth of equal height divided by a shallow semicircular notch; anterior tooth straight, directed posteriorly. Metaventral process short, wide, with posterolateral angles rounded and produced. First abdominal ventrite with thick, high carina along its entire length medially, straight in lateral aspect. Fifth ventrite strongly raised at the sides of small apical notch, which is medially set with two contiguous, diverging teeth. Lateral margins of abdominal ventrites finely crenulate. Meso- and metaventer with pubescence on basal two-thirds, distal limit briefly oblique. Protarsus of male with two basal tarsomeres bearing stiff hairs which are not expanded to form a pad.

Male genitalia (Fig. 15C) with basal piece about twice as long as wide, half of total length. Parameres strongly narrowed in apical third, apices weakly directed towards sternal side; sternal margin bearing a short row of long hairs on the subapical concave part. Median lobe shorter than parameres; in lateral aspect strongly curved towards the tergal side, subapically swollen with angular projection followed by a deep semicircular notch, narrowed apex directed towards the sternal side; in tergal aspect the subapical swelling spindle-shaped, with a median groove.

Etymology.

This species is named after the type locality, "Corozo Pando".

Distribution.

Venezuela (Apure, Guárico).

Remarks.

Nothing is known about the biology of this species. Most specimens were collected at light.