Dasybasis collagua González, 2014

González, Christian R., 2014, Two new species of the genus Dasybasis Macquart, 1847, from Chile (Diptera: Tabanidae: Diachlorini), Zootaxa 3893 (2), pp. 293-300 : 296-299

Dasybasis collagua González sp. n.

( Figs. 6–10 )

Material examined. Holotype ♀, Chile, Iquique Province, Collagua , 23.IX.1951, LE Peña. (20º02’40’’S / 68º51’07’’W). Paratypes: 2 ♀ with same dates. Holotype and paratypes in Instituto de Entomología collection, Univ. Metropolitana de Ciencias de la Educación, Santiago, Chile.

Diagnosis. Medium-sized (7.5–8.5 mm), dark gray species; front wide, with vestigial ocelli; with abundant long gray hairs, without bands; maxillary palpus short yellowish, bearing yellowish gray tomentum and long whitish hairs; antenna brown; mesoscutum dark gray, with long whitish hairs, without narrow longitudinal pale stripes; Wing hyaline, without appendix on R4; abdominal tergites dark gray dorsally, with long, grayish hairs, longer laterally.

Description. Length 7.5–8.5 mm; wing 7.0–8.0 mm (n = 3). Head: eye dark grayish, without bands, with abundant long gray hairs. Front dark gray, with brownish tomentum mostly on the ocellar triangle, bearing long gray hairs. Front wide, parallel-side, frontal index 1.57. Frontal callus light brown, rectangular, with dorsal projection, touching eyes and subcallus with a few short gray hairs ( Fig. 6 ). Posterior border of the head gray; vertex with abundant black - gray hairs. Subcallus gray, tomentose, with sparse, short gray hairs. Clypeus and gena gray tomentose, with long whitish hairs. Beard with long whitish hairs. Scape of antenna brown, with long erect black hairs, on dorsal surface. Pedicel light brown, tomentose, with long erect black hairs on dorsal and ventral surfaces. First flagellomere dark brown rounded on dorsal surface; apical flagellomeres dark brown ( Fig. 7 ). Maxillary palpus short yellowish, bearing yellowish gray tomentum and long whitish hairs. Proboscis and labellum dark brown, labellum, short and fleshy. Thorax: mesoscutum dark gray, with long whitish hairs, without narrow longitudinal pale stripes. Notopleural lobe pale dark gray, with long black hairs. Scutellum dark gray, with long grayish hairs laterally; disc with short black hairs ( Fig. 8 ). Pleura gray, tomentose with long and abundant grayish hairs. Legs brownish. Coxa, femora and tibia with long black hairs. Tarsus with short black hairs. Wing hyaline, without appendix on R4 ( Fig. 9 ). Basicosta bare. Halter dark brown. Calypter concolorous with base of wing. Abdomen: dark gray dorsally, with long, grayish hairs, longer laterally on tergites; posterior border of tergites with narrow grayish hind margins and whitish hairs. Tergite I with narrow grayish tomentose median posterior spots ( Fig. 10 ). Sternites brownish - grayish, mostly brownish haired.

Male: Unknown

Variability. The three specimens are clearly conspecific, there is some variation, especially in length and abundance of ocular pilosity, length of pilosity of maxillary palpus, and length of pilosity of abdominal terga.

Etymology. The specific name is a noun in apposition taken from type locality.

The morphological differences between D. collagua and other species of Dasybasis are shown in table 2.

Figures

FIGURES 6 – 10. Female of Dasybasis collagua sp. n. 6. Head in frontal view. 7. Head in lateral view. 8. Mesoscutum. 9. Wing. 10. Abdomen in dorsal view. Scale bar = 1 mm.