Exetasis Erichson

Barneche, Jorge Adrian, Gillung, Jéssica Paula & González, Alda, 2013, Description and host interactions of a new species of Exetasis Walker (Diptera: Acroceridae), with a key to species of the genus, Zootaxa 3664 (4), pp. 525-536 : 527-529

Exetasis Erichson

Figs. 2 , 3 , 9.

Diagnosis. Body not arched; coloration non-metallic; head hemispherical, much smaller than thorax width; two ocelli present; eyes densely pilose; antennae inserted on the top of the head, adjacent to ocellar tubercle; eyes not contiguous above antennae, contiguous below; palpus absent; proboscis very short; flagellum elongate, slightly tapered; scapes separated; subscutellum small, not enlarged, barely visible; costa circumambient; wing costal margin straight; radial veins straight; R1 not inflated at pterostigma; R2+3 present; R4+5 present as a single vein, usually reaching wing margin; cell r4+5 present, narrowly elongate, closed; crossvein 2r-m present; M1, M2 and M3 present; M3 separate to margin or fused to CuA1, cell m3 usually absent (except in E. calida and E. jujuyensis sp.

nov.); medial veins usually reaching wing margin; discal cell completely closed; CuA2 fused to A1 before wing margin, cell cu-p petiolate; wing microtrichia present at least on costal cell; abdominal tergites smooth, rounded; abdomen rounded, cylindrical, with similar width to thorax.

Key to Exetasis species

1 M3 not fused to CuA1, cell m3 absent ( Fig. 2 A)............................................................. 2.

- M3 fused to CuA1, cell m3 present ( Fig. 2 B, C)............................................................. 5.

2 Abdomen globose; veins M1 and M2 reaching wing margin.................................................... 3.

- Abdomen conical; veins M1 and M2 not reaching wing margin ( Brazil)........................ E. longicornis Erichson.

3 Vein M3 reaching wing margin....................................................... E. eickstaedtae Schlinger.

- Vein M3 not reaching wing margin ( Brazil)................................................................ 4.

4 Antennae longer than head height ( Brazil)................................................ E. brasiliensis Carrera.

- Antennae as long as head height ( Brazil).................................................... E. tumens Walker.

Figures

FIGURE 2. Exetasis wings. A. E. brasiliensis Carrera; B. E. jujuyensis Gillung sp. nov.; C. E. calida Wiedemann (modified from Wiedemann 1830, plate VII, fig. 2 b). Scale line = 1 mm.

FIGURE 3. Exetasis jujuyensis Gillung sp. nov. A. lateral view; B. dorsal view.