Microdacne nardia Skelley, Leschen & Liu, 2021

Skelley, Paul E., Leschen, Richard A. B. & Liu, Zhenhua, 2021, New Australian Erotylinae with notes on Dacnini (Coleoptera: Cucujoidea Erotylidae), Zootaxa 4948 (3), pp. 363-380 : 373-374

Microdacne nardia Skelley, Leschen & Liu , new species

Figures 23–25 , 31

Diagnosis. A member of Microdacne as defined above, distinguished from the other species with the sublateral sulcus of the pronotum vague, close to the lateral margin, tibiae black with pale base and being from Mount Nardi, Night Cap National Park, New South Wales.

Description. Length 3.0 mm; width 1.5 mm. Body, antenna and legs generally black, except antennal base, antennomere 11, palpi, tibial bases and tarsi tan; elytra with a basal band not touching suture that leaves no brown spot at base of humerus ( Figs. 23–25 ), band on apical third reduced to fine line.

Head broad, dorsal interocular distance = 6× ocular width in dorsal view; surface with distinct setose punctures, sparse and fine medially, becoming denser and coarser laterally and anteriorly; clypeus with anterior margin narrow; gena and lateral gula with scattered coarse punctures same size as facets; mentum transverse, width = 3.1× length; anterior margin of plate bluntly angled at middle. Antennomeres shortly, sparsely setose; antennomere 11 broadly oval, obliquely truncate apically.

Pronotum strongly convex, widest near middle; punctures of central disc coarser than on head, diameter of fac- et, reduced laterally; anterior margin deeply emarginate next to anterior angle, strongly projecting medially; lateral margin with fine marginal bead; sublateral groove present along medial half, separated from margin by distance> 1/3 diameter of eye, groove not basally connected to groove of posterior marginal bead ( Fig. 31 ); posterior marginal bead strong medially, with few coarse punctures in groove either side of mid-line, groove ends close to posterior angle, not present at posterior angles.

Elytra strongly convex, short, length = 1.1× width; base nearly straight; strial punctures small, distinct on disc, absent laterally; minute punctures with short setae widely scattered over surface. Prosternal process nearly parallelsided, moderately arcuate, narrowing posteriorly, almost truncate apically, medial knob bluntly rounded. Mesoventrite lateral tubercles more closely set, distance between them = 1× basal width, central concavity evenly rounded. Abdominal ventrite 1 with coxal lines absent, evident only as small angulation on anterior marginal line.

Genitalia not dissected; normally curved protibial base indicates specimen is female.

Material examined. The female holotype of Microdacne nardia ( Figs. 23–25 , 31 ) label data: “[white paper, printed] 28.33S 153.17E NSW / Nightcap N.P. 700m / Mt. Nardi, Newton Dr. / 791 4 Jan. 1987 / A. Newton & M. Thayer ” // “[white paper, printed] warm temperate rainf. / FMHD #87-178 Berlesate leaf & log litter” // “[orange paper with camera symbol] ANIC / Image” // “[red paper, printed] HOLOTYPE ♀ / Microdacne / nardia / Skelley, Leschen, Liu” ( ANIC) .

Etymology. The species name is based on Mt. Nardi, where this species was collected, with the suffix “-ia” meaning “of Nardi”.

Figures

FIGURES 23–28. Microdacne spp.: 23–25) Microdacne nardia sp. nov., holotype, habitus; 23) dorsal view; 24) ventral view; 25) lateral view; 26–28) Microdacne styxia sp. nov., holotype, habitus; 26) dorsal view; 27) ventral view; 28) lateral view. Scale bar = 1.0 mm.

FIGURES 29–32. Microdacne spp., holotypes, anterolateral dorsal oblique view of head and pronotum: 29) M. gloriousa; 30) M. lamingtonia; 31) M. nardia; 32) M. styxia. Scale bar = 1.0 mm.