Hydrochus argutus Knisch

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 : 40

Hydrochus argutus Knisch

Figs. 5 , 67 , 70

Hydrochus argutus Knisch 1921: 3

Hydrochus johannapietersenae Makhan 1995 ; Oliva (1996); confirmed Perkins (2019a)

Originally described from Brazil. Locality and deposition data also published for Ecuador and Peru ( Perkins 2020b, c). Habitus and male genitalia images are given in Perkins (2019a, c). New records from Bolivia, Brazil and Paraguay are given below. This species is a member of the H. argutus species group (map, Fig. 67 ).

Material examined (63): Bolivia: Beni, 40 km E San Borja, Estacion Biologica Beni, Estancia El Porvenir, 6–8.ix.1987, leg. W. E. Steiner (2 NMNH) ; Santa Cruz, 60 mi. N. Santa Cruz, Saavedra Exp. Sta. , 27–30.xii.1959, leg. Robert Cumming (8 NMNH) ; Okinawa , 6.vi.1958, leg. E. Pinckert (8 CAS) ; Prov. Sara , 2 km NW of Santa Rosa, 21.ii.1969, leg. A. Martinez & R.E. Woodruff (13 NMNH) . Brazil: Mato Grosso, Caceres , MT., (16°4’S, 57°41’W), 2–4.xii.1955, leg. M. Alvarenga (3 CAS) ; Rio Bento Gomes (Pantanal); Flussabschnitt bei Periquito , (15°54’S, 56°33’W), 1.i.1993 – 30.xii.1994, leg. E. Stuhr (30) (2 NMW) ; Varzea, Grande County, Cuiaba , Parque de Exposicao , 28.v.1972, leg. R. Williams (1 NMNH) ; Brazil , Mato Grosso do Sul, Corumbá (c. 29 km SE) on BR-262 -19.3062 -57.60382, 25.vi.2018, Drying marsh with abundant vegetation and detritus, leg. Hamada and team, BR18-0625-02A (3 INPA, SEMC) . Paraguay: Dep. Alto Paraguay, Madreion , 15.v.1995, leg. U. Drechsel (20 NMW) ; Dep. Caaguazu, Tayao , 7.iii.1999, leg. U. Drechsel (1 NMW) ; Dep. Concepcion, Est. San Luis, (23°24’23’’S, 57°26’4’’W), 8.ix.1997, leg. Drechsel (2 NMW) .

Figures

FIGURE 5. Dorsal habitus of Hydrochus species in study area.

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

FIGURES 67–68. Geographical distributions. 67. H. argutus species group. 68. H. cracentis.