Hydrochus variabilis 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 : 53

Hydrochus variabilis Knisch

Figs. 5 , 65

Hydrochous variabilis Knisch 1921: 2

Originally described from Brazil. Additional locality and deposition records published for Venezuela ( Perkins, 2019c). Habitus and male genitalia images are given in Perkins (2019a, 2019c). New locality and deposition records for this very commonly collected species, from Bolivia, Brazil and Paraguay, are given below.

Material examined (349): Bolivia: Beni, 1.7 km E of San Borja , (14°52’7’’S, 66°43’53’’W), 15.vii.1998, leg. K. B. Miller (54 SEMC) ; 3.4 km W of San Borja , (14°52’57’’S, 66°46’3’’W), 14.vii.1998, leg. K. B. Miller (1 SEMC) ; 40 km E. San Borja, Estacion Biologica Beni, Palm Camp at Rio Curiraba , (14°44’S, 66°40’W), 6– 8.ix.1987, leg. W. E. Steiner (2 NMNH) ; 7 km SW Trinidad , elev. 163 m (14°52’12’’S, 64°57’32’’W), 18.vii.1998, leg. K. B. Miller (1 SEMC) ; Magdalena, No locality data, elev. 155 m (13°15.202’S, 64°2.56’W), 16.viii.2004, leg. Andre Megroz (3 NMW) ; Santa Cruz, 60 mi. N. Santa Cruz, Saavedra Exp. Sta. , 27–30.xii.1959, leg. Robert Cumming (9 NMNH) ; Ayacucho, 13–14.v.1969, leg. P. & P. Spangler (92 NMNH); K 97 nr. Buena Vista , 6.xi.1971, leg. H. P. Brown (1 NMNH) ; Potrerillos del Guenda, Preserva Natural , elev. 370 m (17°40’S, 63°27’W), 1–4.x.2007, leg. Wappes & Morris (1 SEMC) ; Prov. Sara , 2 km NW of Santa Rosa, 21.ii.1969, leg. A. Martinez & R.E. Woodruff (4 NMNH) ; Santa Cruz, 11–12.v.1969, leg. P. & P. Spangler (9 NMNH) . Brazil: Bahia, Brumado, Ibitira , ca. 22 km E on BR-30 (-14.23308 -41.90501), 556m, 27.ii.2018, roadside pond, mud substrate with marginal vegetation, leg. Benetti & Team, BR 18-0227-02A (8 INPA, SEMC) ; Guanambi , 10 km S on BR-122 (-14.31889 -42.78635), 530m, 27.ii.2018, densely vegetated pond, leg. Benetti & Team, BR 18-0227-03A (1 INPA) ; Morro do Chapéu , BA-422, E of Ventura (-11.65164 -40.95309), 706m, 24.ii.2018, marsh/pond in cattle pasture, leg. Benetti & Team, BR 18- 0224-04A (1 INPA) ; Piatã, Vilarejo Palmerinha (-12.81936 -41.8124), 1000m, 25.ii.2018, reservoir, recently with water, vegetated margins, leg. Benetti & Team, BR 18-0225-02A -. (2 SEMC) ; Mato Grosso, Caceres , MT., (16°4’S, 57°41’W), 1–30.xii.1955, leg. M. Alvarenga (1 NMNH) ; Corumba , 14–23.xii.1919, leg. R. G. Harris (2 NMNH) ; same locality, 21–23.ii.1954, leg. Gans & Pereira (11 NMNH) ; Sete Lagoas , 1–30.iii.1963, leg. F. Werner, Martins, Silva (1 NMNH) ; Varzea, Grande County, Cuiaba , Parque de Exposicao -., leg. no collector or date given on label (2 NMNH) ; same locality, 18.iii.1972, leg. W. H. Whitcomb (8 NMNH) ; same locality, 28.v.1972, leg. R. Williams (10 NMNH) ; 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 (14 INPA, SEMC) ; 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 (1 INPA) ; Dois Irmãos do Buriti , (c. 5 km NW) on MS-162 (-20.63497 -55.32535), 308m, 27.vi.2018, Large pond/lake in cattle field, leg. Hamada and team, BR18-0627-03A -. (4 SEMC) ; Dois Irmãos do Buriti, Palmeiras (c. 7 km S) on MS-450 (-20.51369 -55.42803), 240 m, 22.vi.2018, Pond in field, lots of marginal and submergent/ emergent vegetation, leg. Hamada and team, BR18-0622-01A (10 INPA, SEMC) ; Miranda (c. 9.5 km SW) on MS-339 (-20.32119 -56.42563), 131 m, 26.vi.2018, Marsh area along side stream, leg. Hamada and team, BR18-0626-03A (6 INPA, SEMC) ; Minas Gerais, Monte Azul, Serra do Espinhaço, c. 7 Km E of Monte Azul (-15.17067 -42.80351), 970m, 28.ii.2018, margins of forested stream, leg. Benetti & Team, BR 18-0228-02A (1 INPA) ; Pirapora , 1–30.xi.1975, leg. M. Alvarenga (1 CNC) ; Rio de Janeiro, Icatiaia , temp. mud puddle, 17.iv.1960, leg. Borys Malkin (21 NMNH) ; Rio Grande do Sul, Bossoroca, Arroio Piratinim , (28°31’50.84’’S, 54°57’40.75’’W), 6.ix.2015, leg. Benetti,C.J.; Pes, A.M.; Hamada, N. & Dantas, G. (3 INPA) ; Barra do Angico; Açude no pasto, (28°32’7.4’’S, 54°57’39.7’’), 22.viii.2015, leg. Benetti,C.J.; Pes, A.M.; Hamada, N. & Dantas, G. (8 INPA) ; 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 (12 INPA, SEMC) . P araguay: Alto Parana, Estancia Dimas , (25°33’S, 55°13’W), 24–25.xi.2004, leg. U. Drechsel (18 NMW) ; same locality, 17–22.ii.2005, leg. U. Drechsel (16 NMW) ; same locality, 1–3.vii.2005, leg. U. Drechsel (1 NMW) ; Dep. Concepcion, Stillwasser des Arroyo Toro Paso, Seitenam ( Uferschlamm ), (23°51’S, 56°46’W), 25.x.2002, leg. U. Drechsel (1 NMW) ; Dep. Pte. Hayes, Puerto Galileo , (25°8’S, 57°50’W), 27–29.viii.2005, leg. U. Drechsel (6 NMW) .

Figures

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

FIGURES 65–66. Geographical distributions. 65. H. variabilis. 66. H. ducalis.