Hexarhopalus (Hexarhopalus) iwani, Purchart, Luboš, 2010

Purchart, Luboš, 2010, Review of the genus Hexarhopalus Fairmaire, 1891 (Coleoptera, Tenebrionidae, Stenochiinae) from Borneo with description of new species, Zootaxa 2476, pp. 1-13 : 5-6

Hexarhopalus (Hexarhopalus) iwani sp. nov.

( Fig. 4 )

Type locality. Borneo, Sarawak, Gunung Mulu NP.

Type material. Holotype. (♂ BMNH): SARAWAK: 4th Division, Gn. [Gunung] Mulu NP // nr. [near] Camp 4, c. 1800m // under bark of fallen trees // P.M. Hammond & J.E. Marshall, v-viii. 1978, B.M. 1978-49.

Condition of holotype: right middle tarsus missing.

Differential diagnosis. As individuals of this species possess partly corrugated surface of the elytra and transversely connected interstriae, it belongs, within the entire genus Hexarhopalus , to the H. sculptilis and H.

birmanicus group. It is, however very easily distinguishable by the following characters: entire surface of pronotum smooth (without punctures), lateral carina of pronotum obliterated, some elytral interstriae costate (in both above mentioned species dorsal surface of pronotum at least partly punctate, lateral carina strongly developed, elytral interstriae convex, but not costate).

Description. Size of holotype 10.3 x 4.3 mm. Dull, brown, with dark brown head and pronotum. Antennae, maxillar palpi, clypeus and legs pale brown. Body elongate oval, glabrous.

Head smooth, micropubescent, shagreened. Clypeus, genae and frons simply and finely punctate. Narrower than pronotum in ratio 1:1.5. Frontoclypeal sulcus on the base U-shaped, deep, almost reaching the clypeal margin. Distance between eyes 1.4 times as wide as their diameter (DV). Ocular sulcus normally developed, deep. Vertex very slightly depressed centrally. Antenna slender, approx. 1.1 times as long as pronotum.

Pronotum shagreened and smooth. Slightly transverse, broadest at middle, PW:PL ratio is 1:0.85. Sides of pronotum rounded, posterior half narrowed towards the base of pronotum. The latter rimmed and slightly obliquely truncate anteriad to posterior angles. Anterior two thirds with two large swellings situated dorsolaterally. The space between swellings shallowly depressed midlongitudinally. Oblique indentation on posterior angles short and deep. Lateral carina extremely fine and almost obliterated, bent upwards anteriorly and creating fine rim of anterior angles of pronotum. Anterior margin of the latter obliterated in the middle.

Elytra ovoid, broadest at middle. 1.3 times as long as their width and 2 times longer and 1.3 times as wide as pronotum. The base of the latter strongly carinated with transverse costa. Elytral suture flat. Each elytron with three strongly raised and slightly corrugated elytral interstriae. These end at the beginning of elytral declivity and continue with row of large tubercles. Second and third costae coalescent with transverse basal costa of elytra. Space between each interstriae formed by two more or less regular rows of hole-like punctures with transverse wrinkles. The space between third (outer) interstriae and epipleura with three rows of punctures. Elytral disc slightly convex (LV). Elytral declivity moderately steep. Scutellum triangular.

Prosternum, prosternal process, mesoventrite and metaventrite smooth and glabrous. Metaventrite 0.75 of length of mesocoxa. Abdominal ventrites smooth, micropubescent.

Legs shiny, smooth, simply and finely punctate, micropubescent. Femora glabrous. Apical half of tibiae with relatively long yellowish setae underneath. Tarsi sparsely micropubescent above and with brush-like yellowish setae underneath.

Distribution. Borneo, Sarawak, Mt. Mulu NP.

Etymology. Named in honour of my dear colleague Dr. Dariusz Iwan ( Poland), specialist on Tenebrionidae and head of the Museum and Institute of Zoology (Polish Academy of Sciences).

Figures

FIGURES 1 – 6. Habitus, dorsal view. 1. Hexarhopalus barclayi sp. nov. (holotype); 2. H. becvari sp. nov. (holotype); 3. H. ferreri sp. nov. (holotype); 4. H. iwani sp. nov. (holotype); 5. H. murudensis sp. nov. (holotype); 6. H. rolandi sp. nov. (holotype).