Actenomeros Winterton & Irwin, 1999b

Winterton, Shaun L., 2011, Review of the stiletto fly genus Actenomeros Winterton & Irwin (Diptera, Therevidae, Agapophytinae), ZooKeys 120, pp. 55-63 : 57

Actenomeros Winterton & Irwin, 1999b

Type species:

Actenomeros corniculaticaudus Winterton & Irwin, 1999b: 280.

Diagnosis.

Head sub-spherical; frons grey to gold pubescent; minute, dark setae sometimes present; frons flat to rounded, width sexually dimorphic, male frons narrower, but eyes not contiguous; occiput concave; two-three poorly defined rows of postocular macrosetae, rarely a single row in female; antenna length shorter than head; scape and pedicel short cylindrical, with strong dark setae; flagellum conical, compressed laterally, style terminal; sternopleuron glabrous medially; legs pale yellow, tarsi darkened distally; mid coxa without setae on posterior surface; hind femur with dark, anteroventral setae sub-apically; fore and hind femora without velutum patches; scutal chaetotaxy: np, 3-4; sa, 2; pa, 1; dc, 2-4; sc, 1; wing cell m3 open; abdomen black, male often with extensive abdominal velutum, female often with triangular patches of velutum laterally on segments; male genitalia without velutum patches on ventral surface of gonocoxites; gonocoxite with outer process present, often long, upward directed and horn-like; articulated gonocoxal process greatly reduced or absent; ventral lobe of gonocoxite sometimes greatly enlarged; hypandrium triangular, glabrous, fused to gonocoxites laterally; gonocoxal apodeme relatively short; distiphallus narrow, straight; dorsal apodeme of parameral sheath ‘T’ -shaped; ejaculatory apodemes relatively small, narrow; ventral apodeme forked; female genitalia with A1 and A2 acanthophorite spines well developed; tergite 8 with narrow process on anterior margin; furca sclerotized in a narrow ring; three spherical spermathecae; spermathecal sac shape trilobate, spermathecal duct arrangement paired, one spermathecal duct joining to each spermathecal sac duct or rarely alternating along common spermathecal sac duct ( Actenomeros intermedia ).

Comments.

Winterton et al. (1999b) noted that this genus superficially resembles Nanexila but is differentiated by 2-3 rows of postocular setae and male genitalic features such as a reduced or absent articulated gonocoxal process and sometimes a large horn-shaped outer process on the gonocoxite. The remaining species in the Nanexila atricostalis species-group (i.e. Nanexila atricostalis Winterton & Irwin and Nanexila jimrodmani Winterton) retained in Nanexila have a well-formed articulated gonocoxal process and can be distinguished from Actenomeros species using the key to Australasian genera in Winterton (2011). The horn-like process on the gonocoxites is only present in Actenomeros corniculaticaudus and Actenomeros onyx. Males are unknown for Actenomeros aureilineata comb. n.and Actenomeros intermedia comb. n.; females of these two species are described by Winterton et al. (1999b).

Included species.

Actenomeros aureilineata (Winterton & Irwin) comb. n., Actenomeros budawang sp. n., Actenomeros corniculaticaudus Winterton & Irwin, Actenomeros intermedia (Winterton & Irwin) comb. n., Actenomeros onyx Winterton & Irwinand Actenomeros paradoxa (Winterton & Irwin) comb. n.

Key to Actenomeros species