Delopleurus krikkeni Frolov, 2014

Frolov, Andrey V., 2014, Revision of the genus Delopleurus Boheman (Coleoptera: Scarabaeidae: Scarabaeinae) with description of new species from Africa, Journal of Natural History 49 (3), pp. 129-154 : 148-149

Delopleurus krikkeni Frolov , sp. nov.

( Figure 6A–D )

Diagnosis

This species can be easily separated from other Delopleurus species by sparsely punctate to impunctate disc and base of pronotum. Its pygidium is similar to that of D. fossatus sp. nov. but differs in having convex basal border distinctly widened medially ( Figure 6B ). From D. fossatus sp. nov. it also differs in having larger eyes (in dorsal view).

Description

Holotype, male. Body strongly convex, black, glabrous, length 4.6 mm ( Figure 6A ).

Clypeus quadridentate. Two medial teeth acute, lateral ones right-angled. Clypeal surface coarsely punctate in anterior part and laterally, frons densely punctate (punctures separated by one to two puncture diameters).

Pronotum about two times wider than long. Anterior and lateral margins distinctly bordered, base feebly bordered laterally. Disc and base of pronotum impunctate, sides relatively densely punctate.

Elytra trapezoidal, as wide as long, shiny. Stria relatively deep, with punctures 1.5–2 times larger than striae width. Elytral intervals convex, with minute punctation.

Anterior tibiae with three outer teeth, without a small acute tooth between first outer tooth and apical spur. Anterior tibial spur bifurcated apically.

Pygidium with relatively strongly convex disc separate by deep circular fossa from border. The apical border wider medially and somewhat tapering laterally; apical border somewhat tuberculate in the middle ( Figure 6B ).

Parameres in lateral view with small processes ( Figure 6C ).

Paratype, male. Differs from the holotype in being slightly larger (length 4.8 mm) and having only anteromedial part of pronotal disc impunctate.

Female unknown.

Distribution

The locality where the holotype was collected is uncertain (Adrian Davis, pers. comm.). In 1896, ‘ Samburu’ might refer to a large area to the northwest of Mount Kenya and to the south of Lake Turkana, that was occupied by the Samburu people. But it might also be the railway station (3°46 ʹ S, 39°16 ʺ E) on the railroad Mombasa–Nairobi. This latter locality is some 100 km east-northeast of the locality where the paratype was collected, Mkomazi Game Reserve ( Figure 6D ).

Etymology

The species is named after Jan Krikken (Naturalis, Leiden).

Type material

Holotype, male with labels ‘ Samburu [ KENYA] 30.X to 20.XI. [18]96’, ‘ B. E. Africa C. S. Bretton 98-12’, ‘diff. from the others Krikken 1975’ ( BMNH) . Paratype, male: TANZANIA: Mkomazi GR, Ibaya Camp , unburnt grassland, pitfall traps, 7–8. IV.1995, J.G. Davies leg. ( BMNH) .

Remarks

Two new species are described in this work from the Eastern Arc Region, D. krikkeni sp. nov. and D. naviauxi sp. nov. The former species is known from two males and the latter from two females only. I believe that these specimens are not conspecific because the male specimens lack a characteristic small tooth apicad of the first major outer tooth on the anterior tibae, which is found in the D. naviauxi holotype. Sexdependent modifications of the legs are common in the Scarabaeinae but found in the males only. I think that this additional tibial tooth is sex-independent and should be present in the males of D. naviauxi sp. nov.

Figures

Figure 6. Delopleurus krikkeni sp. nov., holotype. (A) habitus; (B) pygidium; (C) aedeagus in lateral view and internal sac; (D) locality map.