Grouvellinus acutus, Bian & Jäch, 2018

Bian, Dongju & Jäch, Manfred A., 2018, Revision of the Chinese species of the genus Grouvellinus Champion, 1923 (Coleoptera: Elmidae). The G. acutus species group, Zootaxa 4387 (1), pp. 174-182 : 181

Key to males of the Chinese species of the Grouvellinus acutus species group

1 Apex of hind tibia with a conspicuous broad appendage ( Fig. 1a ); apex of penis abruptly attenuate subapically ( Figs 9–10 )................................................................................................ G. acutus

- Apex of hind tibia without such appendage, apex of penis more or less gradually tapering toward apex.................. 2

2 Ventral sac of penis well developed, ejaculatory duct with denticulations ( Fig.12 )........................ G. denticulatus

- Ventral sac of penis weakly developed, ejaculatory duct without denticulations ( Fig. 15 )................... G. fujianensis

Figures

FIGURES 1–4. Habitus, 1–2 dorsal and ventral view of Grouvellinus acutus sp. nov., male, holotype; 1a G. acutus sp. nov., hooked apical appendage on male hind tibia; 3–4 dorsal and ventral view of G. denticulatus sp. nov., male, holotype. Scale bar= 0.5 mm.

FIGURES 9–14. Male genitalia of 9–11 Grouvellinus acutus sp. nov., holotype; 12–14 G. denticulatus sp. nov., holotype. 9, 12 ventral view; 10, 13 dorsal view; 11, 14 lateral view. Scale bar = 0.1 mm.

FIGURES 15–17. Male genitalia of Grouvellinus fujianensis sp. nov., holotype, 15 ventral view, 16 dorsal view, 17 lateral view. Scale bar = 0.1 mm.