Diaclina muehlei, 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 : 503-504

Diaclina muehlei sp. nov.

( Figs. 5 , 18)

Holotype (♂): Rwanda, Nyakabuye , 28.X.–3.XI.1983, leg. H. Mühle, HNHM.

Description: Body length 4.5 mm. Ovate, blackish brown, shining; borders of pronotum, lateral borders of elytra paler brown. Punctures of dorsal surface without setae, punctures of head and pronotum with a few micro- setae. Head outline continuous, not interrupted between clypeus and frons; apical margin of epistome straight, not 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 nearly reaching the base of pronotum, with six distal antennomeres forming kind of club; 2 nd antennomere as wide as long; 3 rd elongate, about 2.5 times as long as wide; antennomeres 6–10 serrate, distal antennomere rounded. Pronotum transverse, width/length ratio 1.8, surface distinctly convex; widest shortly behind the middle. Anterior margin not emarginate, basal margin bisinuate, basal and lateral margins finely bordered, distal margin unbordered in the middle. Anterior corners rounded, posterior corners nearly rectangular. Pronotal disc with dense, partly confluent and larger punctation as on head, subbasal longitudinal impressions indistinct. Propleura with rough and confluent punctuation, with microsetae, surface smooth. Prosternal process not prominent. Elytra ovate with nearly parallel sides, base as wide as pronotal base. Punctural rows without striae, only somewhat diminishing posteriorly, scutellar striole absent, punctures of the rows similar as those on the pronotal disc; all intervals nearly flat, without punctation but feebly wrinkled; lateral margins in dorsal view visible over entire length until apex; humeral angles indistinct. Scutellum large, triangular. Abdominal ventrites with distinct punctation throughout, with microsetae, laterally slightly wrinkled. Tibiae gradually and faintly dilated towards apex, without external keels or other modifications. Aedeagus with triangular apicale and acute tip (Fig. 18).

Diagnosis: D. muehlei sp. nov. can be recognised by the combination of the following characters. Pronotum distinctly convex, width/length ratio 1.8, surface with rough and nearly confluent punctuation, and lateral margins of pronotum widely separated from the convexity of the pronotal disc. See also diagnosis of D. ashantica sp. nov., and identification key below

Etymology: Named in honor of Hans Mühle (Munich), collector of the holotype.

Distribution: Known only from the type locality in Rwanda.

Figures

FIGURES 1–6. Dorsal view of African species of Diaclina. 1 D. ashantica sp. nov., holotype HNHM. 2 D. brevicollis, lectotype NHMB. 3 D. gracilis, non-type South Africa SMNS. 4 D. minuta, lectotype NHMB. 5 D. muehlei sp. nov., holotype HNHM. 6 D. ovalis (holotype decellei syn. nov.) MRAC. Scale: 1 mm.