Hydrochus spanglerorum

Perkins, Philip D., 2021, Taxonomy of water beetles in the genus Hydrochus Leach, 1817, from Bolivia, Brazil and Paraguay (Coleoptera: Hydrochidae), Zootaxa 4994 (1), pp. 1-93 : 12

H. spanglerorum species group

Figs. 1 , 24 , 52 , 53 , 70

Members of the H. spanglerorum species group are recognized by the combination of the following characteristics: 1) large size, length ca. 4.20–5.10 mm; 2) head with very convex frons disc, bordered on each side with deep longitudinal groove (e.g., Fig. 52 ); 3) legs with densely, deeply punctate femora and tibiae; 4) 3 rd and 5 th elytral interstriae raised, costate to subcostate, throughout length, not additionally raised at usual area of callus; 5) male genitalia very robust, lacking parameres, lacking distal flagellum or process, and having articulated basal orifice. Three species are currently known, all in South America: H. accinctus n. sp., H. spanglerorum Perkins , and H. colossus n. sp. ( Fig. 53 ).

Figures

FIGURE 1. Dorsal habitus of Hydrochus species in study area.

FIGURE 52. Hydrochus colossus n. sp., habitus and female genital segments of holotype.

FIGURE 70. Pictorial aid to species groups of Hydrochus from Bolivia, Brazil and Paraguay, using male genitalia. Not to same scale.

FIGURES 24–25. Habitus and male genitalia of holotypes. 24. Hydrochus accinctus n. sp. 25. Hydrochus amazonicus n. sp.

FIGURES 53–54. Geographical distributions. 53. H spanglerorum species group. 54. H collaris species group.