Diaclina grandis, Schawaller, 2019

Schawaller, Wolfgang, 2019, The species of the genus Diaclina Jacquelin du Val (Coleoptera: Tenebrionidae: Alphitobiini) from Sub-Saharan Africa, Zootaxa 4609 (3), pp. 499-508 : 502

Diaclina grandis sp. nov.

( Figs. 10 , 15)

Holotype (♂): Congo, Kiwu , Lwiro, Lemera, 16.VII.1956, leg. T. Jilly, SMNS.

Description: Body length 7.0 mm. Elongate parallel, blackish brown, shining; borders of pronotum, lateral borders of elytra, and scutellum paler reddish brown. Punctures of dorsal surface without setae and microsetae. Head outline continuous, not interrupted between clypeus and frons; apical margin of epistome shallowly emarginate in the middle; fronto-clypeal suture indistinct. Genal canthus not projecting beyond contours of eyes, with the outlines nearly continuous with the outlines of the latter. Eyes large, constricted by genal canthus, dorsal part smaller than ventral part. Antennae not reaching the base of pronotum, with six distal antennomeres forming kind of club; 2 nd antennomere slightly wider than long; 3 rd elongate, nearly three times as long as wide; antennomeres 6–10 serrate, distal antennomere rounded. Pronotum transverse, width/length ratio 1.3, surface feebly convex; widest in the middle. Anterior margin shallowly emarginate, basal margin bisinuate, basal and lateral margins finely bordered, distal margin unbordered in the middle. Anterior corners rounded, posterior corners rectangular. Pronotal disc with finer and sparser punctation than on head, subbasal longitudinal impressions distinct. Propleura with similar fine punctation without setae, surface indistinctly wrinkled. Prosternal process not prominent. Elytra elongate with parallel sides, base as wide as pronotal base. Punctural rows without striae, diminishing posteriorly, scutellar striole absent, punctures of the rows larger than those on the pronotal disc; all intervals nearly flat, with fine irregular punctation; lateral margins in dorsal view visible over entire length until apex; humeral angles indistinct. Scutellum large, triangular. Abdominal ventrites with very dense and fine punctation throughout, bare, basally and laterally slightly wrinkled. Tibiae gradually and faintly dilated towards apex, without external keels or other modifications. Aedeagus with short and broad apicale and rounded tip (Fig. 15).

Diagnosis: Diaclina grandis n.sp. can be recognised by the large body size and the elongate parallel elytra. It is similar to Diaclina parallela , but this species is smaller in the average around 5 mm (not 5–7 mm as noted by Gebien 1921), has the male head with tubercles, the pronotum much more convex, and the aedeagus with a narrower apicale (Fig. 16). See also note below under an unidentified single female of similar large size from Kenya.

Etymology: The name refers to the large body size, unusual in the genus.

Distribution: Known only from the type locality in Congo.

Figures

FIGURES 7–10. Dorsal view of African species of Diaclina. 7 D. cameruna, non-type Kenya SMNS. 8 D. parallela, non-type South Africa SMNS. 9 Diaclina sp. ♀, Kenya TMSA. 10 D. grandis sp. nov., holotype SMNS. Scale: 1 mm.