Hydraena reflectiva, Perkins, 2014

PERKINS, PHILIP D., 2014, A revision of the water beetle genus Hydraena Kugelann for southern Africa (Coleoptera: Hydraenidae), Zootaxa 3758 (1), pp. 1-92 : 18-19

Hydraena reflectiva , new species

Figs. 35 (habitus), 37 (aedeagus), 74 (map)

Type material. Holotype (male): South Africa: Eastern Cape Province, Transkei: S. coast, Dwesa forest reserve, shore washing, forest, 32° 17' S, 28° 50' E, 3 iii 1985, Endrödy-Younga (#2181) ( TMSA) . Paratypes (33): South Africa: Eastern Cape Province, Same data as holotype (27 TMSA) ; Free State Province, 15 km NW Klaserie, Guernsey Farm , woodland evening car netting, elev. 500 m, 24° 5' S, 31° 15' E, 19–31 xii 1985, S. & J. Peck (1 CMNO) ; Suid Kaap River ; GEN 145J, marginal vegetation, 25° 44' S, 30° 59' E, (1 AMG) ; KwaZulu-Natal Province, Hluhluwe Game Res. , shore washing, shade, 28° 5' S, 32° 4' E, 27 xi 1992, Endrödy-Younga (#2861) (3 TMSA) ; Hluhluwe Game Res. , shore washing, swift water, 28° 5' S, 32° 4' E, 19 xi 1992, Endrödy-Younga (#2832) (1 TMSA) .

Differential diagnosis. Recognized by its very small size (ca. 1.17 mm) and its very finely sparsely punctate dorsum that is very shiny and lacks foveae PF1, PF2, and PF4 ( Fig. 35 ). The aedeagus shows some relationship to that of H. genumorpha ( Figs. 9 , 37 ), but that species is larger (ca. 1.39 mm) and much more strongly punctate dorsally, and has foveae PF2 ( Fig. 7 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.17/0.50; head 0.20/0.30; pronotum 0.30/0.40, PA 0.34, PB 0.36; elytra 0.72/0.50.

Dorsum of head piceous; pronotum brown around dark brown macula; elytra dark brown; legs brown; maxillary palpi testaceous.

Frons punctures ca. 1xef, larger and denser near eyes than medially; interstices weakly shining, 0.5–1xpd laterally, 1–3xpd medially. Clypeus mcr laterally, very finely sparsely punctulate medially. Mentum and postmentum finely sparsely punctulate, interstices shining. Genae slightly raised, shining, without posterior ridge.

Pronotum laterally slightly emarginate behind middle; anterior margin straight behind eyes, emarginate behind frons, scintilla absent; very finely sparsely punctate, punctures on disc slightly smaller than those of frons, interstices strongly shining, 2–10xpd, punctures slightly larger and denser at anterior and posterior; PF1, PF2 and PF4 absent; PF3 very shallow.

Elytra weakly arcuate laterally; summit of posterior declivity at ca. posterior 1/3; lateral explanate margin narrow; on basal 1/3 punctures ca. 1xpd largest pronotal punctures, punctures becoming finer and more widely spaced toward posterior. Intervals not raised, strongly shining, on basal 1/3 ca. 3–6xpd, as are interstices between punctures of a row. Apices in dorsal aspect very weakly separately rounded, in posterior aspect margins forming very shallow angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 1.5/1/4/4. P1 laminate; median carina sinuate in profile. P2 l/w ca. 2/1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow, parallel, weakly raised, located at sides of moderately deep median depression. Metaventrite with low midlongitudinal carina between intercoxal process and median depression. AIS width at slightly arcuate posterior margin ca. 2x P2. Protibiae moderately arcuate, gradually increasing in width from base to moderately wide apex. Meso- and metatibiae slender, straight. Abdominal apex symmetrical; last tergite with very small apicomedian notch. Female (microslide mount, n=1): last tergite moderately sharply rounded, with minute apicomedian notch, ca. 16 hooked, closely set setae, in irregular row; gonocoxite not midlongitudinally divided, apical margin moderately sharply rounded, low transverse ridge evident at border of microreticulation; spermatheca simple, type C shape.

Etymology. Named in reference to the markedly shining dorsum.

Distribution. Currently known from only four rather widely separated localities in eastern South Africa, coastal in Eastern Cape and Kwazulu-Natal Provinces, and two localities more inland in Free State Province ( Fig. 74 ).

Figures

FIGURE 7. Hydraena genumorpha, holotype, dorsal and lateral habitus.

FIGURE 35. Hydraena reflectiva, holotype, dorsal and lateral habitus.

FIGURES 8–9. Aedeagi of holotypes.

FIGURES 36–37. Aedeagi of holotypes.

FIGURES 71–74. Geographical distributions of Hydraena species.