Microcenoscelis caeca, Schawaller, Wolfgang, 2015

Schawaller, Wolfgang, 2015, Microcenoscelis n. gen. (Coleoptera: Tenebrionidae: Ulomini) from tropical Africa, with description of a blind species from Zimbabwe, Zootaxa 4027 (3), pp. 437-441 : 439

Microcenoscelis caeca n. sp.

( Fig. 1 )

Holotype (♀). Zimbabwe, Manicaland, 20 km SE Mutare, Vumba (= Bvumba) Mountains, 1800 m, 28.–29.XI.2006, leg. P. Schüle, SMNS.

Description. Body length 2.8 mm. Surface shining, unicoloured light brown. Head including clypeus with regular punctation similar as on pronotum, distances of punctures equal to 1–4 diameters; punctures without setae; clypeal suture invisible; clypeolabral membrane exposed; eyes absent; antennomeres gradually widening distally without separated club, shape of antennomeres see Fig. 1 , antennomere 3 not prolonged and as long as antennomere 4; mentum without distinct setae. Pronotum subquadrate, 1.1x as wide as long, widest in anterior third and parallel in the two basal thirds, anterior corner rounded and not protruding, posterior corners rectangular; basal margin sinuated, basal and distal margins unbordered, lateral margins finely separated; surface with similar punctation as on head, without any impressions; propleura with similar, not confluent punctation as on head and pronotum. Wings reduced. Elytra elongate parallel, 1.5x longer than wide, not covering last abdominal tergite, with nine punctural rows in weak striae, punctures of the rows somewhat larger than pronotal punctures, punctures around elytral tip with microsetae, intervals flat and with a row of finer, but distinct punctures. Prosternum slightly prominent. Abdominal ventrites with denser punctation as on pronotum and partly confluent, last ventrite unbordered. Legs without peculiarities and similar as in the female of M. minuscula . Unfortunately, only a single female is available, thus sexualdimorphic characters are unknown. But, according to characters in both sexes of M. minuscula , the male protibiae of M. caeca n. sp. are supposed to be not regularly rounded as in the female, but with a feeble angle, and the male protarsi are not widened. Aedeagus unknown, only female available.

Diagnosis. Both species of the genus ( Figs 1–2 ) can be separated not only by the absence/presence of eyes and wings, but also by a different shape of the pronotum (in M. caeca n. sp. 1.2x as wide as long, basal margin sinuated; in M. minuscula 1.3x as wide as long, basal margin straight), and by a different number of spines of protibiae (5–6 in M. caeca n. sp., 8–9 in M. minuscula ).

Etymology. Caecus in Latin means blind, referring to the lacking eyes.

Figures

FIGURES 1 – 2. Dorsal view of Microcenoscelis n. gen. 1 M. caeca n. sp., holotype female, Zimbabwe. 2 M. minuscula (Ardoin, 1969) n. comb., non-type female, Ivory Coast. Scale: 1.0 mm.