Dasybasis antillanca, González, Christian R., 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 : 294

Dasybasis antillanca sp.n.

( Figs. 1–5 )

Material examined. Holotype ♀, Chile, Osorno Province, Antillanca (40º46’35’’S / 70º12’16’’W), 2.II.1992, coll. C.R. González. Paratypes: 3 ♀ with same dates. Holotype and paratypes in Instituto de Entomología collection, Universidad Metropolitana de Ciencias de la Educación, Santiago, Chile. Flies of this species were attracted to human collectors.

Diagnosis. Medium-sized (14.5–15.5 mm), brown species; front wide, with vestigial ocelli; eye with abundant gray hairs, without bands; antenna dark brown; maxillary palpus elongated yellowish, bearing yellowish tomentum and short black–gray hairs; mesoscutum dark gray, with long black and whitish hairs, bearing two narrow longitudinal pale stripes reaching scutellum; wing hyaline, without appendix on R4; abdomen light brown dorsally, with long, yellowish hairs, pale brownish laterally on tergites I and II.

Description. Length 14.5–15.5 mm; wing 13.5–14.5 mm (n = 4). Head: eye dark grayish, without bands, with gray hairs. Front gray, with brownish tomentum mostly on the ocellar triangle, bearing short black hairs. Front wide, parallel-side, frontal index 2.2. Frontal callus shining brown, rounded, with dorsal projection, not touching eyes ( Fig. 1 ). Posterior border of the head gray; vertex with erect black hairs. Subcallus brownish, tomentose, with sparse, short gray hairs. Clypeus and gena brownish tomentose, gena with long black and whitish hairs, black hairs concentrated near subcallus clypeus bearing long whitish hairs and a few long black hairs. Beard with long whitish hairs. Scape of antenna dark brown, and with short and long black hairs on dorsal surface. Pedicel darker and with very short black hairs. First flagellomere dark brown rounded on dorsal surface, apical flagellomeres lighter brown ( Fig. 2 ). Maxillary palpus elongated yellowish, bearing yellowish tomentum and short black–gray hairs ( Fig. 2 ). Proboscis black, labellum black, large and fleshy. Thorax: mesoscutum dark gray, with long black and whitish hairs, bearing two narrow longitudinal pale stripes reaching scutellum. Notopleural lobe pale gray, with long black hairs. Scutellum dark gray, with short black hairs on the disc and long black hairs ( Fig. 3 ). Pleura gray, with long yellowish hairs. Legs brownish, coxa grayish. Femur with long yellowish hairs, tibia shorter and black. Tarsus with short black hairs. Wing hyaline, without appendix on R4.Basicosta bare. Halter light brown. Calypter concolorous with base of wing ( Fig. 4 ). Abdomen: light brown dorsally, with long, yellowish hairs, pale brownish laterally on tergites I and II, posterior border of tergites with distinct narrow grayish hind margins and grayish hairs. Tergites I to VI with broad grayish tomentose median posterior spots. Tergite VII with tomentum and pale grayish pilose ( Fig. 5 ). Sternites brownish, mostly grayish haired.

Male: Unknown

Variability. There is some variation, especially in distribution of black pilosity of the maxillary palpus, the length of the median projection of the frontal callus (longer in some specimens), and color of abdominal terga.

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

The morphological differences between D. antillanca and other species of Dasybasis are shown in table 1.

Figures

FIGURES 1 – 5. Female of Dasybasis antillanca sp. n. 1. Head in frontal view. 2. Head in lateral view. 3. Mesoscutum. 4. Wing. 5. Abdomen in dorsal view. Scale bar = 1 mm.