Disersus dasycolus Spangler & Santiago-Fragoso, 1987

Maier, Crystal A., 2013, A revision of the Larainae (Coleoptera, Elmidae) of Venezuela, with description of nine new species, ZooKeys 329, pp. 33-91 : 37-40

Disersus dasycolus Spangler & Santiago-Fragoso, 1987 Figs 2, 13, 14, 15, 16, 17

For complete description and genitalia illustrations see Spangler and Santiago-Fragoso 1987.

Material examined.

VENEZUELA: Mérida State: "VENEZUELA: Mérida State; 8°35.355'N, 71°13.926'W 1646m; N. of Ejido, Rt. 4 river x-ing; 10.vii.2009; leg. Shepard; gross sample; VZ09-0720-02Z" (3 specimens SEMC). "VENEZUELA: Mé rida State; 8°14.393'N, 71°48.672'W, 1862m; Bailadores; 18.vii.2009; Cascada; de Bailadores - stream margins; leg. Short et al.; VZ09-0718-02A" (1 specimen SEMC). "VENEZUELA: Mérida State; 8°38.006'N, 71°09.762'W, 2037m; Monte Zerpa area; 20.vii.2009; leg. W. Shepard; stream margin; gross sample; VZ09-0720-01Z" (3 specimens SEMC). "VENEZUELA: Mérida State; Rio Montealban, Rt. 4; 19 km. W. Mérida; 20 Feb 1976; C.M. & O.S. Flint Jr." (2 specimens USNM). "Venezuela. Mérida; Mcipo. Rangel. P.N. Sierra; Nevada; La Mucuy; 2200m. 05/07-XI-1992" "Colector:; J. Camacho" (1 specimen MALUZ) "Via Jaji; Me. Vzla; 15-IX-77" "Cols:; J.M. Osario; A. Escalona" (1 specimen MALUZ). "La Pedregosa; Venezuela-Meri-; da. 1800m; 18-IX-1966" C.J. Rosales; J. Salcedo" (1 specimen MIZA). Trujillo State: "Bocono; Venezuela, Tru-; jillo. m.; 21-VII-1974" "F. Fernandez; H.M. Giani" (3 specimens MIZA). "Bocono; Trujillo Venz.; 13-VIII-1964" "E. Osuna; M. Gelbes" (1 specimen MIZA). "VENEZUELA: Trujillo State; 9°11.935'N, 70°45.233'W, 1601m; ca. 6 km E. Monte Carmelo; 22-vii-2009; leg. W. Shepard; VZ09-0722-03Z; gross sample" (1 specimen SEMC). "VENEZUELA, Trujillo; Parque N. Guaramacal; Mpio. Bocono, Laguna; Aguas Negras 1740; msnm. 26 –28/V/1995” "Colectores:; J. Camacho; M. Garcia" (3 specimens MALUZ). "VENEZUELA: Trujillo; Paq. Nac. Guaramacal; Mpio. Bocono Laguna; de Aguas Negras, 1800; msnm. 20-25/VIII/ 1995; Trampa de Luz" "Colectores:; J. Camacho; M. Garcia" (2 specimens MALUZ). "VENEZUELA, Trujillo; Mcipo. Sta. Ana. Via; Bocono-Trujillo 1000; msnm. 28/V/1995" "Colectores:; Garcia, M.; Camacho, J." (18 specimens MALUZ). Lara State: Anzoátegui; (Qda. Guago); Venezuela- Lara; 1440m 13 –16-VI-72” "J. Salcedo; F. Zambrano" (10 specimens MIZA, 2 specimens MALUZ). Barinas State: "Venezuela: Barinas; San Isidro, 14 kms Sur; La Soledad. 1500m; 30 –31-V-1975” "E.E. Dietz; leg." (7 specimens MIZA).

Diagnosis.

Disersus dasycolus is unique among the species of Disersus and can be distinguished from all other species by the fuzzy protibiae of the male (Fig. 17). Males have a patch of dense, long, curly setae on the distal third of the ventral side of the protibia that is found in no other species of Disersus (Fig. 17) (See Spangler and Santiago-Fragoso 1987).

Intraspecific variation.

This species varies slightly in color and size, from a medium to dark brown. Females do not possess the patch of setae apicoventrally on the protibiae, and instead bear setae that resemble those of the other legs.

Habitat and distribution.

Previously, this species was only known from a single specimen collected at blacklight trap in Pastaza Province, Ecuador. Somewhat surprisingly, this species is quite common in streams in the Mérida Andes of Venezuela above 1000m elevation, and seems to prefer stream margins (Fig. 2).

Associated species.

A single species of Hexanchorus , Hexanchorus flintorum sp. n. was collected at the same localities as Disersus dasycolus . Disersus spp. are often collected in conjunction with Hexanchorus spp. as they seem to prefer the same rocky cascades as habitat. Other aquatic beetles collected at the same localities include: Andogyrus spp. ( Gyrinidae ).