Burmacyrtus Grimaldi & Hauser

Grimaldi, David A., Arillo, Antonio, Cumming, Jeffrey M. & Hauser, Martin, 2011, Brachyceran Diptera (Insecta) in Cretaceous ambers, Part IV, Significant New Orthorrhaphous Taxa, ZooKeys 148, pp. 293-332 : 307

Burmacyrtus Grimaldi & Hauser gen. n.

Diagnosis.

A small, primitive acrocerid in Burmese amber easily separated from Schlingeromyia based on the well developed mouthparts; long, fine antennal stylus; dense, fine pilosity on thorax and abdominal tergites; absence of a mediolobus on the pretarsus; absence of tibial spurs; wing apex rounded; and by the venation: Vein C circumambient, cells br and bm completely separated, absence of cells r4+5 and m3, presence of a very large cell d, vein R4 present but vestigial (not connected to R5), veins CuA1 and CuA2 each present, vein A1 vestigial (cell cup not present).

Type Species.

Burmacyrtus rusmithi sp. n., by present designation.

Etymology.

Combination derived from Burma (the pre-junta name for Myanmar) and Cyrtus , nominal genus of Cyrtidae , a formerly used name of Acroceridae .

Discussion.

Derived acrocerid features that Burmacyrtus shares with Schlingeromyia and Recent acrocerids are the following: spherical head with large, holoptic eyes in male; apex of antennal flagellum with simple stylus; presence of a distinct cervical region; wing membrane with fine wrinkling and devoid of microtrichia; and with a large calypter. Apomorphic features in Burmacyrtus that are lacking in Schlingeromyia are fine, dense pilosity; a broadly rounded wing apex; long, fine stylus; and lack (loss) of a mediolobus. The wing shape of Burmacyrtus is similar to that of some Recent acrocerine genera such as Turbopsebius Schlinger, 1972, but the latter genus has cell r4+5 present, veins CuA1+M3 fused, and a complete vein A1, among other features. Like Schlingeromyia , Burmacyrtus is also very basal in the Acroceridae . Some of the derived features in wing venation of the two species in Burmese amber may be due to the very small body size.