Discozantaena drakensbergensis, 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 : 10-11

Discozantaena drakensbergensis new species

( Figures 3 , 14 , 26 )

Type Material. Holotype (male): Lesotho: Drakensberg, Sani Pass Valley, 29° 39' S, 29° 12' E, shore washing, 10 March 1976, Endrödy­Younga, E.­ Y.(#1062); deposited in the TMSA. Paratypes (11): Same data as holotype, (10 TMSA). South Africa, Transvaal Prov., Station 9, headwaters of Wilge River, VAL 641G, stones in current (surbers sampler), 28° 11' S, 29° 33' E — (1 AMG). Representative specimens to be deposited in AMG and MCZ.

Diagnosis. Recognized by the very shining dorsum, the almost non­granulate pronotal discal relief, and the posteriorly acuminate elytra ( Fig. 3 ).

Description. Size (length/width, mm) holotype: body (length to elytral apices) 1.80/ 0.87, head 0.32/0.50, pronotum 0.42/0.75, elytra 1.06/0.87. Dorsum shining, dark brown, head and disc of pronotum piceous; venter dark brown, elytral epipleurae and pronotal hypomeron lighter. Frons disc weakly transversely convex, longitudinally on about same plane as clypeus; very finely sparsely granulate, each granule with minute seta. Clypeus transverse, anterior margin straight, sides rounded, anterior angles obsolete, very finely sparsely granulate. Labrum apicomedian emargination slightly reflexed.

Pronotum very transverse; anterior margin straight median 1/2 with narrow hyaline border; anterior angles sharply rounded; sides arcuate except emarginate before acute, tooth­like posterior angles; posterior margin arcuate except emarginate near posterior angles. Sides minutely denticulate. Disc quite strongly 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; lateral to tenth series broadly explanate almost to apex; sides minutely serrate, pubescence dense, short and overlapping. Ten seriate punctate, but two additional series on explanate margin, series not striate impressed, punctures transversely oval, those near base contiguous longitudinally, becoming little more separated and slightly smaller posteriorly, each with distinct short decumbent seta, serial setae not overlapping, each setal base with minute granule. Intervals impunctate, shining, flat, slightly wider than serial punctures. Sutural margin raised slightly in posterior 1/2. Humeri almost obsolete.

Metasternum with midlongitudinal impression. Thoracic sterna and abdominal ventrites 1–4 and basally 5 clothed with sparse short pubescence.

Aedeagus total length 0.67 mm; mainpiece length 0.38 mm. The mainpiece distal widened area and the large collar are diagnostically shaped. The flagellum is long and forms a corkscrew spiral; the apical 1/5 is weakly sclerotized and its shape can therefore vary depending on the preparation ( Fig. 14 ).

Etymology. Named in reference to the geographical distribution.

Distribution. Presently known from the Drakensberg mountains in Lesotho and Transvaal Province of South Africa ( Fig. 26 ).

Notes. This is a flightless species; the wings are about 1/2 the length of the elytra.

Figures

FIGURE 3. Discozantaena drakensbergensis holotype. Dorsal and lateral habitus.

FIGURE 14. Discozantaena drakensbergensis. Aedeagus of holotype.

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