Hydrochus coeneni Makhan

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 : 42

Hydrochus coeneni Makhan

Figs. 4 , 71

Hydrochus coeneni Makhan 1992: 102

Originally described from Brazil. Locality data and deposition records have also been published for Peru ( Perkins 2020c). Habitus and male genitalia images are given in Perkins (2020c). New records from Bolivia, Brazil and Paraguay are given below.

Material examined (41): Bolivia: Santa Cruz, Ayacucho , 13–14.v.1969, leg. P. & P. Spangler (8 NMNH) . Brazil: Mato Grosso, Rio Caraguata , elev. 400 m (21°48’S, 52°27’W), 1–30.ix.1953, leg. Fritz Plaumann (1 NMNH) ; Brazil , Mato Grosso do Sul, Anastácio, Aquidauana (c. 5 km S) on MS-174 (-20.53416 -55.76038), 166m, 27.vi.2018, Small shallow pond with dense vegetation, leg. Hamada and team, BR18-0627-02A (10 INPA, SEMC) ; Brazil , Rondonia, Presidente Medici, Ji-Paraná (27 km SW), Rio Urupa (-11.03618 -62.14465), 135m, 10.vii.2018, Series of ponds and fairly large marsh area with abundant vegetation, leg. Short, BR 18-0710-01C (10 INPA, SEMC) . Paraguay: Dep. Concepcion, Stillwasser des Arroyo Toro Paso, Seitenam ( Uferschlamm ), (23°51’S, 56°46’W), 25.x.2002, leg. U. Drechsel (12 NMW) .

Remarks. I have examined the holotype, including the male genitalia, of H. coeneni (RBINS) . The male genitalia has the tips of the parameres sheared off—by a previous worker. The remainder of the male genitalia, including the basal piece, are distinctively shaped, allowing the identification. The male genitalia drawing of Makhan (1992) shows the paramere tips to be present, but the drawing is very generalized, and only one view is given.

Figures

FIGURE 4. Dorsal habitus of Hydrochus species in study area.

FIGURE 71. Pictorial aid to species groups of Hydrochus from Bolivia, Brazil and Paraguay, using male genitalia. Not to same scale.