Oocyclus zulianus Short & García, 2010

Short, Andrew E. Z. & García, Mauricio, 2010, A review of the Oocyclus Sharp of Venezuela with description of twelve new species (Coleoptera: Hydrophilidae: Laccobiini), Zootaxa 2635, pp. 1-31 : 29-30

Oocyclus zulianus Short & García sp. n.

( Figs. 4 B, 7)

Type material. Holotype: VENEZUELA: Zulia State: female, “ VENEZUELA: Zulia State/ 10 03.058’N, 72 42.074’W, 435 m / Perijá National Park: Toromo/ 31.xii.2005; leg. A.E.Z. Short/ Small stream & seep; AS- 06-001”, “[barcode]/ SM0830811/ KUNHM-ENT”, “ HOLOTYPE / OOCYCLUS / zulianus sp.n. / des. Short & García 2010 ” ( MIZA).

Diagnosis. Smaller species (less than 4.0 mm) ( Fig. 4 B). Posterolateral corners of pronotum broadly rounded. Procoxae not spinose. Elytra without distinct rows of systematic punctures; sparsely covered with fine setae arising from ground punctuation. Elytral suture not raised. Elytral margins not explanate, and with a fringe of long yellow setae.

Among the smaller Venezuelan Oocyclus , the species is most similar to another species from the Guiana Shield region, O. coromoto , (both have rounded posterolateral corners and some dorsal elytral setae), but the ground punctation is much less impressed in O. coromoto ( Fig. 4 B), and the elytral setae less dense and more restricted to systematic punctures.

Description. Size and form. Body length = 3.3 mm. TL/GW = 1.6. Body oval, moderately convex.

Color. Dorsum of head, pronotum, and elytra black with a general faint iridescent green sheen. Anterolateral margins of pronotum without pale patch. Elytra without iridescent maculae. Maxillary and labial palps yellow. Mentum and stipes light to reddish brown, distinctly paler than ventral face of head. Legs, epipleura, lateral margins of prosternum yellowish brown. Abdominal ventrites light brown.

Head. Ground punctation on labrum, clypeus and frons fine, distance between punctures 1.5–3.0× the width of one puncture. Systematic punctures on labrum consisting of several indistinct punctures medially. Frons with an irregular row of systematic punctures mesad of each eye, bearing fine erect setae. Clypeus with a few very indistinct systematic punctures along anterolateral margins, slightly larger than surrounding punctation. Maxillary palps short, about as long as width of labrum; segment 2 slightly bulbous, apical segment slightly longer than penultimate. Labial palps three-fourths as long as width of mentum. Mentum quadrate, anterior margin slightly convex, bearing very fine punctures.

Thorax. Ground punctation on pronotum and elytra composed of moderately fine, evenly distributed punctures of generally uniform size. Ground punctation on pronotum and elytra with short fine, decumbent setae. Pronotal systematic punctures with short fine setae, similar to slightly larger in size to ground punctures, blending with larger ground punctures. Lateral margins of pronotum and elytra with dense row of yellow setae, creating fringed appearance. Posterolateral corners of pronotum broadly rounded. Sutural punctation on elytra absent or unmodified from ground punctation. Elytra without distinct rows of larger systematic punctures, as they blend uniformly with ground punctation. Prosternum with a low, weak median carina, which is elevated anteromedially, the elevation without spine-like setae or long setae. Elevated process of mesoventrite raised to a point medially, with two lateral and one posterior carina sloping downward from the apex; with 2 thickened spine-like setae. Metaventrite with small oval glabrous area posteromedially, about as long as wide, length of glabrous area slightly less than half the length of metasternum. Procoxae with dense, fine short pubescence; without thickened setae or spine-like setae. Protibiae each with 7 spine-like setae on dorsal face.

Abdomen. Ventrites with scattered setae of varying lengths; each ventrite with irregular rows of long erect setae which are distinctly longer than the longest setae on metaventrite.

Etymology. Named after the state in Venezuela (Zulia) from which it is known. Treated as a noun in apposition.

Distribution. Known only from the type locality in the Serranía de Perijá ( Fig. 7 ).

Remarks. The single known specimen was collected in hygropetric habitat formed when a small stream spilled over a cement bridge.

Figures

FIGURE 4. Dorsal and lateral habitus of Oocyclus species found in the Venezuelan Guiana Shield region. A) O. petra sp. n., B) O. coromoto sp. n.; C) O. floccus sp. n. Scale bar = 2.0 mm.

FIGURE 7. Distribution of Oocyclus species in Venezuela.