Gyrinus Geoffroy, 1762

Lee, Dae-Hyun & Ahn, Kee-Jeong, 2015, A taxonomic review of the Gyrinidae (Coleoptera) in Korea, ZooKeys 509, pp. 87-107 : 89-91

Taxon classification Animalia Coleoptera Gyrinidae

Genus Gyrinus Geoffroy, 1762 Figs 15-22

Gyrinus Geoffroy, 1762: 194. Type species: Dytiscus natator Linné, 1758.

Diagnosis.

Head (Fig. 15) about 3.0 times wider than long, with micro-reticulation. Frons with two rounded depression (arrows in Fig. 15). Antenna with 9 antennomeres, antennomere 2 rugous with sparse punctures, 9 with compact short setae on apico-lateral part. Clypealium with long setae on antero-lateral part. Galea 1-articled. Pronotum with transverse depression on median parts (arrow in Fig. 16), lateral parts rugous, anterior margin slightly sinuate, posterior margin slightly rounded, anterior angle acute, posterior angle acute. Elytron (Fig. 16) with 11 punctato-striae and with out compact setae, apical margin rounded; subelytral suture present (arrow in Fig. 17); epipleura reached on lateral part of sternite VII, anterior part of epipleura rounded. Prosternum transverse; anterior margin slightly rounded (Fig. 18). Prosternal process (Fig. 18) linear-form, gradually broad at posterior part. Metaventrite (Fig. 19) elongated, diamond-shaped, flattened; anterior part very acute; lateral parts curved upwardly. Tergite VIII (Fig. 20) with compact long setae and posterior margin rounded. Sternites III–VII (Fig. 21) with weak depression on lateral part. Sternite VII (Fig. 21) with long setae on lateral margin. Sternite VIII (Fig. 22) with long setae on postero-lateral parts and posterior margin rounded.