Austrocoenia aczeli Wirth 1970

Austrocoenia aczeli Wirth

Austrocoenia aczeli Wirth, 1970:8

DIAGNOSIS.—Generally pollinose, whitish gray to gray but with some brown coloration dorsally; ocelli arranged in equilateral triangle; tarsi with venter yellowish, hind basitarsus mostly yellowish except for thin linear dorsal gray stripe; wing mostly hyaline, veins brown except for yellowish costa, subcosta, and basal portions of other veins; structures of male and female terminalia as in Figures 4–6.

DESCRIPTION.—Medium-sized to large shore flies, length 3.67 to 5.08 mm; generally gray.

Head (Figures 1, 2): Head width-to-height ratio averaging 1:0.73. Mesofrons generally gray to grayish brown but frequently with some bluish, greenish, or charcoalish coloration immediately around ocelli; parafrons generally darker in coloration than mesofrons, more bluish to charcoalish fronto-orbits nearly concolorous with mesofrons. Antenna mostly gray but with small patches blackish gray or whitish gray. Facial unicolorous, whitish gray, becoming slightly darker dorsally. Eye-to-cheek ratio averaging 1:0.65. Gena concolorous with face. Maxillary palp blackish gray.

Thorax (Figure 3): Mesonotum dark bluish gray to whitish gray but mostly grayish brown to brown; 2 darker stripes on either side of acrostichal setae extending posteriorly no further than level of transverse suture; acrostichal track mostly brownish, frequently with whitish stripe between; scutellum with disc mostly grayish brown to brown; pleural areas distinctly lighter in color than mesonotum, becoming whitish gray to white ventrally. Femora and tibiae concolorous, whitish gray; basal 2 tarsomeres pale, rufous to yellowish orange; apical tarsomeres becoming darker, grayer. Wing (Figure 66) veins yellowish brown to yellowish anterobasally, otherwise brownish; membrane mostly hyaline, occasionally lightly infuscated, brownish, or slightly milky; costal vein index averaging 1:0.18; M1+2 vein index averaging 1:0.88. Halter yellowish.

Abdomen: Generally unicolorous, gray. Male and female terminalia as in generic diagnosis and Figures 4–6.

TYPE MATERIAL.—Holotype male, labeled: “R[epublica] A[rgentina]. SANTA CRUZ Cabo Buen Tiempo Gallegos 29–II–(1)953 Coll: Biraben.” Allotype female and 31 paratypes (7 , 24 ; TUCU, BM(NH), USNM): with same label data as the holotype. The holotype, allotype, and several paratypes are in the Instituto Miguel Lillo, Tucumán, Argentina. The holotype specimen is double mounted (minute nadel in cork base) and is in good condition.

OTHER SPECIMENS EXAMINED.—ARGENTINA: Santa Cruz Province: Piedrabuena, 5 km NW, 130 m elevation, 25 Nov 1966, M. Irwin and E. I. Schlinger (11 , 4; USNM). CHILE: Magallanes Province: Laguna Amarga, 4 km W, 51°00′S, 72°48'W, 300 m elevation, 7 Dec 1966, M. E. Irwin and E. I. Schlinger (1; USNM).

Calocoenia Mathis, 1975:78 [type-species: Paracoenia platypelta Cresson, original designation and monotypy].

DIAGNOSIS.—Specimens of Calocoenia closely resemble those of Paracoenia but may be distinguished from the latter and other genera of Scatellini by the following combination of character states: Generally dark colored; mesofrons subshiny to shiny, inconspicuously setulose; 2 pair of large lateroclinate fronto-orbital bristles; inner and outer vertical bristles both well developed; paravertical seta well developed, about one-half length of cruciate vertical bristle; arista pectinatė, dorsally branching rays subequal to one-half width of third antennal segment; face with interfoveal carina, but dorsal crease not as distinct as in specimens of Paracoenia; eye subspherical to subelliptical, oriented at slight oblique angle to general plane of head; acrostichal setae uniformly small, hairlike, seriated into 2 rows that extend to base of scutellum; 5 pair of dorsocentral bristles (2 + 3); humeral callus with 2–3 larger setae, bristlelike; supra-alar bristle well developed, subequal to anterolateral postalar bristle; scutellum setose dorsally, with 2 pair of lateral bristles; with dorsum subplanate; costal margin with evenly spaced spinelike setae distinct from remaining setae; radial stem vein bare; male fifth abdominal tergum slightly wider than long; terga generally unicolorous; surstylus as angulate processes extending from ventral margin of epandrium, contiguous medially; aedeagus well developed, acutely pointed apically; female ventral receptacle with small operculum, conformation subtrapazoidal in lateral view, extending process much longer than width of operculum.