Criorhina Meigen, 1822

Li, Hu, Huo, Ke-Ke & Li, Bao-Guo, 2020, A new species of the flower fly genus Criorhina Meigen (Diptera: Syrphidae) from mainland China, Zootaxa 4803 (1), pp. 169-176 : 170

Criorhina Meigen, 1822

Criorhina Meigen, 1822: 236 . Type species: Syrphus asilicus Fallén, 1816 (designation by Westwood, 1840: 136)

Penthesilea Meigen, 1800: 35 . Type species: Musca ruficauda de Geer, 1776 . Suppressed by I.C.Z.N., 1963: 339

Distribution. Holarctic and Oriental Regions.

Diagnosis. Criorhina can be recognized by the following combination of characteristics: 1) eyes bare; 2) males dichoptic; 3) head in frontal view subtriangular; 4) face with a conspicuous facial knob; 5) face strongly produced antero-ventrally; 6) basoflagellomeres short, wider than long; 7) vein R 4+5 almost straight; 8) anterior cross vein (rm) strongly oblique, reaching the anterior margin of the discal cell in the distal half.

Remarks. As a group of honey-bee and bumblebee mimics, Criorhina is similar to several other genera. The face of Criorhina flower flies elongates strongly antero-ventrally, while in Lycastris the lower part of face (mouth edge) obviously pushes out anteriorly to form a “beak” with a very slender proboscis. In Criorhina , wing cell Sc has not additional cross veins, but it has in Lycastris . The shape of face and the metafemur weakly enlarged make Criorhina different from Brachypalpus . The males narrowly dichoptic but not shortly holoptic, the basoflagellomere clearly wider than long, and the antero-ventrally elongated face serve to distinguish Criorhina from Blera .