Genus Gnatholea Thomson

Gnatholea Thomson, 1861, Class. Ceramb., 375 (type-species : G. eburifera Th., 1861) loc. cit. - Pascoe, 1869, Trans, Ent. Soc. Lond., ser 3, 3: 530. - Gahan, 1906b, Fauna British India, Col. 1: 110.

Diagnostic characters : Head with subtransverse depression between frons and clypeus; mandible of male with crest and much larger than female; two pairs of ivory-like smooth callosities on elytron.

Key to species of Gnatholea in Sarawak

1.    Body ferrugineous; callosities broad, roundish and ivory white. - subnuda LACORDAIRE, 1869
Eye black; body flavotestaceous; callosities elongated, opaque. - brevidiehli sp. nov.

Gnatholea subnuda LACORDAIRE

Entirely ferrugineous except callosities; mandible, palpi, entire head, antennae, prothorax, elytra, sterna and legs including tarsal segments ferrugineous; callosities yellowish eburneous.

Head rather short; mandible triangular, base very wide, dorsal cristate, external surface pubescent; clypeus acinacicate, feebly produced over labrum; a deep subtransverse depression between clypeus and frons with two foveae at side; lower gena as deep as eye lobe; antennifer not produced, flatten in front; vertex slightly raised between antennal insertion, convex, granulose; a weak median sulcus that terminate at neck. Antenna fringed from segment 2 onwards, dorsal and lateral piliferous, ventral capillate; scape accrescent, apex rounded; segment 3 twice as long as scape; 4 shorter than 3; 5 subequal to 4. Prothorax transverse, anterior margin incurved, posterior sinuate; side rounded, with two protuberances, one in the middle and the other in front; disc granulo-punctate, side of median with two obtuse tubercles; side of fore intercoxal process sinuate, truncated and abrubtly bent at posterior. Scutellum linguiform, apex truncate. Elytron 5 X as long as broad; gradually narrow, declivent, truncated at apex; sutural and angular tooth not prominent; disc somewhat asperated, dotted with substriate punctures near base; granulate at apex; callosity near base biguttate, the external one larger; another biguttate callosity middle of elytron, outer lobe inclined. Undersurfaces densely pubescent; mesosternum puncto-striate. Legs : fore femur fusiform; femora incurved especially near base; posterior margin of mid­intercoxal process notched; first hind tarsal segment shorter than 2 + 3 united.

Measurement: Length 25.1 mm (); breadth 6.7 mm ()

Distribution: Laos; Peninsular Malaysia (Malacca); Sarawak. 

Known habitat : forest clearings.

Note : the tip of this specimen seem to be discolored and looks testaceous instead.

Material examined : 1 [B14] UPM campus, Bintulu, Bintulu Div., 13.II.1992 (UNIMAS Coll.).

Gnatholea brevidiehli sp. nov.

Head subvertical; mandible triangular-cristiform, punctate and pubescent at base; withdrawn under labrum when close; apical segment of maxillary and labial palpi truncated; clypeus elevated with deep transverse grooves between labrurn and frons; gena oblique externally, lower margin angulated; anterior margin of gula transversely striate; frons short, sparsely pubescent; vertex and neck flat, punctulate; eye widely separated, subequally emarginated. Antenna slender, filiform; 1.5 X longer than body ; segment 3 onwards ventrally fringed with long bristles, diminish towards apex; scape thicken at apex, punctulate; segment 3 longest, 2.5 X as long as scape; 4 - 6 subequal; 7 - 11 subequal, half as long as 3. Prothorax robust; as wide as elytra; hexagonal; side with a feebly tubercle; disc subglabrous, minutely granulated and pubescent. Scutellum triangular, small. Elytron 6 X as long as broad; parallel, gradually narrow at 1/4 from apex, transversely truncated with a small sutural and angular spine; disc covered with minute pubescence, 2 pairs of callosities; coarsely punctate on 2/3 basal half, punctulate to subglabrous on 1/3 of apex; callosity near base oblong-biguttate; another biguttate callosity at middle, the outer lobe 1/3 X longer than the inner one; two feebly costae running through these callosities and extended posterior. Undersurfaces pubescent; 5 transverse abdominal sgment, 1 - 3 of equal width. Legs normal; fore femur subfusiform; middle and hind femora long and slender, linear; hind femur extended to tip of elytra; first hind tarsal segment as long as 2 + 3 united.

Holotype (For. Dept. Coll.) [A.S. 80-0277] Niah, Min Div, 17.V.80., Alexander Sayak. Length 12.8 mm (); breadth 3.5 mm ()

Distribution : Sarawak

Note  : Very similar to Gnatholea diehli HUDEPOHL, 1992 especially the hexagonal prothorax and punctate elytra, differ in smaller in size (28.3 mm long, 7.5 mm wide for G. diehli), robust prothorax and the posterior callosities that has a much longer outer lobe.