Genus Zatrephus Pascoe

Zatrephus Pascoe, 1857, Trans. Ent. Sec. Lond., ser 2, 4 : 94 (type-species : Z. pannosus Pasc., 1857) loc. cit.; 1869, Trans. Ent. Soc. Lond., ser 3, 3 : 523. - Thomson, 1864, Syst. Ceramb., : 446 (loc. cit.). - Lacordaire, 1869, Gen. Col., 8 : 267 (loc. cit.). - Aurivillius, 1912, Coleopt. Cat., 39 : 62. - Gressitt & Rondon, 1970, Pac. Ins. Monogr, 24 : 88.

Diagnostic characters : head short, vertical in front; lower eye lobe triangular; antennae stout, as long as body in , shorter in ; segment 3 - 5 bulbous at apex; 6 - 10 expended externally and angulate ectoapically; intercoxal process of prosternum tuberculate and vertical at posterior; elytra elongated, convex, obliquely truncate with a angular cusp.

Note : this genus is very similar to Rhytidodera except in having a tuberculate fore intercoxal process and bulbous basal antennal segment (Gressitt & Rondon, 1970).

 Key to species of Zatrephus in Sarawak:

1.   Pubescence on elytra made up of 2 colors, producing scattered dots among tawny pubescence on disc; base of elytra with a knob near scutellum; frons without fovea; scape punctate; pronotum with 3 rounded protuberance at each side of median - pannosus PASCOE, 1857
Pubescence on elytra of the same texture and color, evenly distributed producing glistering patters; base of elytra without knob near scutellum; frons not elevated, with 2 foveae; scape carinate, rugose; pronotum transversely rugose - spinosus BRONGNIART, 1890

Zatrephus pannosus PASCOE

Zatrephus pannosus Pascoe, 1857, Trans. Ent. Soc. Lond., ser 2, 4 : 94 (loc. cit.); 1869, Trans. Ent. Soc. Lond., ser 3, 3: 524. - Aurivillius, 1912, Coleopt. Cat., 39: 62.

Body dark fuscous; elytra with dense and even flavo-lacteous pubescence intermixed with aggregated tawny pubescence scattered as spots on disc; prothorax fuscous with dew scattered fulvous woolly patches.

Head vertical; mandible short, incurved entire length; labrum elliptical; anterior of frons elevated, punctate, oblique below antennal support; the latter widely separated, slightly raised. Antenna extended to 1/2 of elytra; scape punctulate; segment 3 - 5 subequal, bulbous, shorter than scape; 6 – 10 obliquely expanded and terminate at angle ectoapically; last segment as long as 10. Prothorax distinctively narrower than elytra; longer than broad, gradually narrow towards apex; side rounded; pronotum with a slightly raised area behind middle; side with 3 raised blunt protuberance, surface of the 2 posterior one rugose; vermicular laterally. Elytron 4.5 X as long as broad; base with a knob between humeral angle and suture; disc uneven, dented side of suture at above middle; tip abruptly oblique at 1/4 from apex; apex truncate, angular cusp obscure.

Measurement: Length 28 mm (); breadth 8 mm ()
Distribution: Sarawak 
Material examined: 1 unlabled (SM Coll.)

Zatrephus spinosus BRONGNIART

Head and prothorax fuscous with yellowish tawny pubescence, denser on head; antennae castaneous, basal segments fuscous, entirely pubescent; pronotum with 2 tawny longitudinal stripes a little off median; slightly further outward a fuscous glabrous patch, attenuate posteriorly; elytra bright fulvescent with golden glistering pubescence; undersurfaces evenly clothed with dense pale luteo-fulvous pubescence.

Head vertical; labrum sinuate; frons not elevated with 2 deep foveae side of middle below antennal support. Antenna a little longer than body in ; scape carinate dorsally; segment 3 - 5 compressed, transverse, apex bulbous; 6 - 10 subequal, 1.5 X as long as 3; last segment 2 X as long as 3. Prothorax broader than long; widest at middle, side concave; apical constriction narrower than basal; pronotum transversely rugose, interrupted medianly with a longitudinal depression or groove; prosternum. with 3 dimidiate rings separated by 2 transverse groove. Elytron 6 X as long as broad; uniformly pubescent; disc even, apical half gradually decline; apex truncate, angular cusp large and produced horizontally.

Measurement : Length 26.0 mm() ; breadth 6.0 mm ()
Distribution : Sarawak 
Material examined : 1 unlabled (SM Coll.)