Discozantaena brevicollis, Perkins, Philip D., 2005

Perkins, Philip D., 2005, A revision of the South African endemic humicolous beetle genus Discozantaena Perkins and Balfour­Browne (Coleoptera: Hydraenidae), Zootaxa 915, pp. 1-48 : 12-13

Discozantaena brevicollis new species

( Figures 5 , 16 , 28 )

Type Material. Holotype (male): S. Cape Mt., Helderfontein S., 1220m, 33.56S — 20.52E, sifted, alpine marsh, 10 March 1979, leg. Endrödy­Younga (#1566); deposited in the TMSA. Paratypes (25): Same data as holotype, (9 TMSA). S. Cape Mt., Helderfontein, 1150m, 33.56°S — 20.52°E, sifted, fynbos, 8 March 1979, leg. Endrödy­Younga (#1561), (12 TMSA). Cape Pr., Knysna, Buffelsnek, berl. litter under shrubs in fynbos, 16–19 December 1979, S. & J. Peck, (#169), (4 MCZ). Representative specimens to be deposited in AMG.

Diagnosis. Recognized by the very transverse, comparatively short pronotum, the emarginate anterior margin of the clypeus, and the male genitalia ( Figs. 5 , 16 ).

Description. Size (length/width, mm) holotype: body (length to elytral apices) 1.71/ 0.79, head 0.32/0.47, pronotum 0.38/0.68, elytra 1.00/0.79. Dorsum brown, explanate margin of pronotum and elytra lighter; venter brown.

Frons flattened but feebly gibbous between oblique foveae, disc with moderately dense granules, moderately shining; decumbent pubescence short but rather dense, small granule at base of each seta, on disc setae directed posteriad, near eyes setae directed mediad. Clypeus very transverse, anterior angles very widely rounded, sculptured and clothed as frons, but slightly less densely. Labrum moderately shining, pubescence very short and sparse; apicomedian emargination slightly reflexed.

Pronotum very transverse; anterior margin very weakly arcuate median 1/2 with narrow hyaline border; anterior angles sharply rounded; sides nearly straight, except emarginate before acute, tooth­like posterior angles; posterior margin arcuate except emarginate near posterior angles. Sides minutely denticulate. Disc roundly elevated between anterior and posterior broadly U­shaped transverse impressions; granules dense in impressions, much finer and sparser on relief separating U­shaped impressions; lateral explanate area shining, with granules about as coarse as those in impressions, but much sparser.

Elytra with anterior angles sharply rounded, sides weakly arcuate to middle, then markedly attenuate to very narrowly truncate apices, sutural apex very minutely produced; external to tenth series broadly explanate almost to apex, moderately shining; sides minutely serrate, pubescence dense and short. Ten seriate punctate, but two additional series on explanate margin, series barely striate impressed, punctures transversely oval, those near base contiguous longitudinally, posteriorly becoming little more separated and slightly smaller, each with distinct short sub­decumbent seta; each setal base with minute granule. Intervals impunctate, shining in clean specimens, flat, slightly wider than serial punctures. Sutural margin raised slightly in posterior 1/2.

Metasternum with low midlongitudinal carina in anterior 1/4, shallow fovea in posterior 3/4. Thoracic sterna and abdominal ventrites 1–4 and basally ventrite 5 clothed with sparse short pubescence.

Aedeagus total length 0.46 mm; mainpiece length 0.35 mm; mainpiece rather uniform in width from base to near distal widened area; flagellum coiled distally, but not forming corkscrew; basal 1/2 stiff, remainder weakly sclerotized and its shape can therefore vary depending on preparation; collar (like D. sepiola and D. tibiovela ) in front of flagellum only; shape of collar, base of flagellum and distal widened area, seen in lateral view, are diagnostic ( Fig. 16 ).

Etymology. Named in reference to the very transverse, short pronotum.

Distribution. Presently known from two localities in southern Cape Province ( Fig. 28 ).

Figures

FIGURE 5. Discozantaena brevicollis holotype. Dorsal and lateral habitus.

FIGURE 16. Discozantaena brevicollis. Aedeagus of holotype.

FIGURES 26 – 28. Discozantaena distribution maps. — 26. D. drakensbergensis. — 27. D. genuvela. — 28. D. brevicollis.