Namibiotrupes penrithae Krikken, 1977

Gussmann S. M. & Scholtz, C. H., 2000, Systematic revision of endemic southern African genera of Bolboceratinae (Coleoptera: Scarabaeoidea: Bolboceratidae), Journal of Natural History 34, pp. 1045-1123 : 1065-1066

Namibiotrupes penrithae Krikken

(®gures 4a±e, 5a±c, 6a, b, 7)

Namibiotrupes penrithae Krikken, 1977a: 166 .

Description

Body length. 9.8±11.8 mm.

Colour. Light brown, forebody distinctly darker.

Head. Labrum (®gure 5b) sloping downward from obsolete transverse carina in anterior third and posterior two-thirds; asetose; anterior margin feebly sinuate. Clypeus (®gure 5a) with vertical incline to anterior transverse carina; anterior carina feebly sinuate in dorsal view, strongly arcuate in frontal view; in males (®gures 5b, 6b) with posterior, transverse bihorned carina; each long, conical horn positioned adjacent to lateral carina; area between horns in frontal view raised and U-shaped; in females (®gure 6a) horns reduced to small tubercles and area between tubercles in frontal view raised but only feebly U-shaped; carina between tubercles only feebly developed; lateral carina in both sexes extending posteriorly from above antennal insertion in a straight line to a point in line with posterior end of eye-canthus. Frons slightly concave. Antennal club (®gure 5a) elliptic, massive, longer than diameter of eye; apical segment strongly ināted, outline of each segment ovoid; basal segment feebly convex, setose over entire surface.

Pronotum (®gure 6a, b). With steep anterior declivity, topped by very feebly bowed transverse carina adjacent to elongate antero-lateral concavities; concavities laterally bordered by one, medially depressed, carinate, elongate protrusion (males) or two separate feebly developed, carinate, elongate protrusions (female); in posterior part with feebly indented midline, the latter lined with a few larger punctures; entire pronotum with ®ne punctation and scattered larger punctures, larger punctures densely spaced only laterally; antero-lateral angle of pronotal margin obtuse; in lateral view most of hypomeron exposed below lateral pronotal margin.

Scutellum. Basal width about 1.16Ölength (®gure 5c); with a few large and very ®ne punctures.

Elytron. Striae moderately impressed, their punctures large and separated by one to two puncture diameters (®gure 5c); intervals with ®ne punctation (approximately three to four punctures between two striae); second stria almost reaching elytral base.

Legs. Protibia ®ve-dentate. Metatibia in lateral view distinctly broadened apically; with knoblike projections randomly spread over basal three-quarters of surface above subapical carina. Metatarsus with several subapical setae on tarsomere 2, with one subapical seta on tarsomere 3 (tarsomeres 4 and 5 missing).

Male genitalia. Aedeagus as in ®gure 4d, e.

Distribution (®gure 7). The species is only known from two localities in the Namib Desert.

Type material examined. HOLOTYPE: l`Gorob Mine, Namib Desert Park, SE 23 15 Cb, 16± 17 Mar 1974 ’/` Namibiotrupes penrithae g. sp. n. J.Krikken ms 1976, Holotype ’ l /`H18019’ /`Holotype’ [black print on red label] ( SMWN) .

Additional material examined (one specimen). Namibia: 1m [dissected], Gobabeb, 23.3S 15.0E [23.34S 15.03E], 408 m, 27.iii.1967 ( TMSA) .

Comments. The male holotype and one female of Namibiotrupes penrithae Krikken remain the only specimens collected to date. The species is easily distinguished from its congeneric species by the large antennal club with the strongly ināted and asymmetrically shaped apical segment. This latter feature, also found in both Prototrupes species but in no other African genera, might be, as Krikken (1977a) suggested, an adaptation to extreme desert conditions. Additional diOEerences between Namibiotrupes penrithae and the other two species are discussed under the latter below.