Genus Ceriomydas Williston

Oeriomydas Williston, 1898: 58. Type-species, fraudulentus Williston (orig. des.).

The original description is as follows:

"Like Mydas J but the abdomen as in Ceria or Oonops . The abdomen is pedunculate, much narrower at the base, broadly expanded and acuminate distally; the first two segments are tapering, the third cylindrical, with parallel sides, and nearly twice as long as wide; the fifth segment is as broad as the thorax, whence the abdomen tapers to a point. The face is more produced downwards than in Mydas) and the labella are larger. There is a marginal cross-vein in the wings, and the hind tibiae are spurred".

In the description of [raudulentue Williston stated "lamella (antennal club) altogether about three-fourths the length of the third joint. - Length 27 mm.".

"One specimen (~), Chapada, Brazil (H. H. Smith). This specimen shows a remarkable mimicry of certain ones of Oonops occurring in the same region".

The female abdomen is narrowed basally in a few species of Mydas . This is probably most evident in Mydas tricinctus Bellardi; in dorsal view tergite 3 is one and one-half times as broad as long.

A photograph of Oeriomydas irouduientus Williston was published by Williston (1908: 18, fig. 3), and Curran (1934: 480). The genus is known only from the type, which could not be located.