Discozantaena genuvela Perkins and Balfour­Browne

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 : 11-12

Discozantaena genuvela Perkins and Balfour­Browne

( Figures 4 , 15 , 27 )

Discozantaena genuvela Perkins and Balfour­Browne, 1994: 124 .

Type Material. Holotype (male): S. W. Cape Mts., Hawequas SE, sifted, elev. 1100 m, 33° 34' S, 19° 8' E, 5 November 1973, Endrödy­Younga (#202); deposited in the TMSA. Paratypes (231): Same data as holotype, (98 TMP). Cape Prov., Cape District, Table Mountain, Wynberg Cave Ravine, sieved from vegetable debris, elev. 822.96 m, 33° 58' S, 18° 25' E, 18 December 1950, Brinck & Rudebeck ( SSAE Stn. 84) — (6 LUM); Cape Town, 33° 55' S, 18° 25' E, Raffray — (1 SAMC); same locality, 33° 25' S, 18° 25' E, 1 January–30 December 1897, L. Peringuey — (12 SAMC); Cape­Cederberg, jeep track, sifted marsh shore, elev. 1130 m, 32° 28' S, 19° 14' E, 7 November 1983, Endrödy­Younga (#2055) — (30 TMSA); Devil's Kloff, sifted, elev. 850 m, 32° 28' S, 19° 6' E, 30 October 1981, Endrödy­Younga (#1909) — (64 TMSA); Kirstenbosch, Table Mountain, humus, ZA 39, 33° 58' S, 18° 25' E, 1–30 November 1960, N. Leleup — (2 TMSA); Piketberg District, (lower) Berg River, near Piketberg; Albany Museum catalog GBG 107D, river, 32° 53' S, 18° 44' E, 11 October 1950, A. D. Harrison — (1 AMG); SW Cape, Grootdrif Farm, ground trap with meat bait, 61 days, 32° 24' S, 18° 27' E, 29 August 1981, Endrödy­ Younga (#1861) — (1 TMSA); Table Mountain, Doline Bats Cave, humus, ZA 43, 33° 58' S, 18° 25' E, 1–30 December 1960, N. Leleup — (4 TMSA); W. Cape, Dwarsberge, sifted litter, 34° 2' S, 19° 1' E, 15 November 1973, Endrödy­Younga (#253) — (5 TMSA); W. Cape, Hawequas, shore washing, 33° 34' S, 19° 8' E, 10 November 1973, Endrödy­Younga (#226) — (7 TMSA). Representative specimens to be deposited in AMG and MCZ.

Diagnosis. Very similar to D. leleupi in form and sculpture ( Figs. 4 , 10 ), but smaller in body size (ca. 1.60 mm vs. 1.77 mm); reliable determinations should be based on the study of the male genitalia ( Figs. 15 , 21 ).

Description. Size (length/width, mm) holotype: body (length to elytral apices) 1.62/ 0.92, head 0.25/0.50, pronotum 0.39/0.72, elytra 1.13/0.92. Dorsum brownish­testaceous, head and disc of pronotum piceous; venter piceo­testaceous. 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 finely microreticulate, moderately shining, pubescence very short and sparse; sinuation of anterior margin slightly reflexed.

Pronotum very transverse; anterior margin weakly arcuate, median 1/2 with narrow hyaline border; anterior angles sharply rounded; sides weakly 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, clothed with moderately dense, short decumbent golden setae, socket of each seta very indistinct but anterior rim raised to form distinct oblong granule, some granules 8­shaped; interstices strongly shining. Lateral depressions with setae and granules less dense than those on disc.

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 posteriorly with narrow but sharply impressed median furrow. Thoracic sterna and abdominal ventrites 1–4 entirely clothed with sparse short pubescence, especially sparse medially, cuticle micropunctulate.

Aedeagus total length 0.60 mm; mainpiece length 0.35 mm; mainpiece gradually widening from near base to distal widened area; flagellum in form of corkscrew spiral; collar wraps around base of flagellum, distinctively shaped ( Fig. 15 ).

Distribution. Presently known from western Cape Province ( Fig. 27 ).

Figures

FIGURE 4. Discozantaena genuvela holotype. Dorsal and lateral habitus.

FIGURE 10. Discozantaena leleupi holotype. Dorsal and lateral habitus.

FIGURE 15. Discozantaena genuvela. Aedeagus of holotype.

FIGURE 21. Discozantaena leleupi. Aedeagus of holotype.

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