Oocyclus sitesi Short & Swanson

Short, A. E. Z. & Swanson, A. P., 2005, A revision of the Oocyclus Sharp of Thailand with description of six new species (Coleoptera: Hydrophilidae), Zootaxa 1078, pp. 1-24 : 13-16

Oocyclus sitesi Short & Swanson , sp. n.

( Figs. 2 , 9–10 , 12 )

Type Locality. Thailand: Kanchanaburi Province, Ampur Thong Pha Phum, 6.3 km W of boarder police station at Ban Padsadoo Klang, 14°32N 98°32E, 568 m.

Type Material. Holotype: Male. “ THAILAND: Kanchanaburi Prv. Amphur / Thong Pha Phum sml. wtrfl 6.3 km W of / Boarder Police Stn. at Ban Padsadoo Klang / rock face 568 m L­463 14°32N 98°32E / 10.IV.2003, UMC & CMU teams”, “ HOLOTYPE / Oocyclus / sitesi / Short & Swanson” ( USNM). Paratypes (9): same data as holotype (9: AEZS, EMBT, ISU, MCZ, NMW, UMRM).

Diagnosis. Posterolateral corners of pronotum evenly rounded. Labrum with row of systematic punctures very dense, nearly forming a median grove. Procoxae without distinct spines. Most similar to O. bhutanicus and O. viridescens , from which it can be distinguished by the distinct rows of setiferous elytral punctures.

Description. Size and Form. Length=3.0– 3.4 mm. EL/EW=1.03. Oval, moderately to strongly convex. Elytra slightly longer than wide. Color. Dorsum black. Head, pronotum and lateral margins of elytra often with mottled bronze to dull yellow iridescence, which varies in intensity and distinctness. Maxillary and labial palpi yellow. Mentum and stipes light to reddish brown, distinctly paler than ventral face of head. Legs, epipleura, lateral margins of prosternum, and posterior half of each ventrite yellow to light brown, with remainder of venter slightly to moderately darker reddish brown. Head. General punctation on labrum, clypeus and frons slightly variable in size from almost undetectable to fine; densely distributed, distance between punctures 0.5–1.5x the width of one puncture. Systematic row of punctures on labrum extremely dense, more or less forming a lateral, shallow median groove, and set with a dense row of long erect yellow setae. 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 and usually bearing short setae. Antennae with scape subequal in length to segments 2–5; first two segments of club subequal in length and apical segment slightly longer. Maxillary palpi very short, slightly shorter than the width of the labrum; segment 2 slightly bulbous, apical segment slightly longer than penultimate. Labial palpi three­fourths as long as width of mentum. Mentum quadrate, anterior margin slightly convex; bearing very fine and scattered punctures, some of which bear fine, long setae. Thorax. General punctation on pronotum and elytra extremely fine and generally uniform in size and distribution. Pronotal systematic punctures distinct, 2– 3 x the size of general punctation and set with a fine recumbent seta; anterior and posterior series each forming an irregular row. Lateral margins of pronotum set with a few sparsely distributed setiferous punctures. Posterolateral corners of pronotum evenly rounded. Sutural punctation on elytra absent or unmodified from general punctation. Elytra with five diffuse rows of setiferous punctures: rows 1–3 with punctures spaced irregularly but linearly and bearing recumbent setae; row 4 more or less a field of irregularly spaced punctures with recumbent to erect setae; row 5 along extreme lateral margin, bearing erect fine setae. Prosternum with median carina along entire length, with an acute tooth anteriorly; without long spines or hairs anteriorly. Mesosternal process with lateral extensions sloping evenly downward; apex set with a few long fine setae. Metasternum with small oval glabrous area posteromedially, about as long as wide, length of glabrous area about 1/5 the total length of metasternum. Pro­ and mesocoxae densely pubescent; without spines. Protibiae with 9–13 spines on dorsal face. Protarsal segments 1–4 small, subequal in length; apical segment ca. as long as segments 1–4 combined. Abdomen. Ventrites 1–4 with two lateral rows of very long, fine setae; longest setae longer than the setae around metasternal glabrous area. Fifth ventrite entire; with dense, uniform setae over entire surface. Aedeagus ( Fig. 2 ) with parameres narrow, outer margins slightly sinuate and bulged at apex. Median lobe narrow and parallel­sided.

Distribution. Thailand; known only from the type series.

Etymology. Named in honor of Robert W. Sites, University of Missouri, who with his students kindly collected, sorted, and provided much of the material on which this revision is based.

Figures

FIGURE 9. Oocyclus sitesi sp. n. (holotype). Dorsal and lateral habitus. Scale bar = 1 mm.

FIGURE 10. Oocyclus sitesi sp. n. (holotype). Ventral habitus. Scale bar = 1 mm.

FIGURES 1 – 6. Oocyclus aedeagi, dorsal views. 1. O. viridescens sp. n. 2. O. sitesi sp. n. (holotype). 3. O. namtok sp. n. 4. O. thailensis sp. n. (holotype). 5. O. sumatrensis d’Orchymont (specimen from Thailand). 6. O. melinoventris sp. n. Scale Bar = 0.18 mm.

FIGURES 11 – 15. Details of Oocyclus. 11 – 12. Thoracic sterna. 11. O. melinoventris sp. n. (holotype). 12. O. sitesi sp. n. (holotype). 13 – 15. Lateral margin of pronotum, with posterolateral corner to the right. 13. O. viridescens sp. n. 14. O. sumatrensis d’Orchymont. 15. O. thailensis sp. n. Scale bar = 1 mm.