Coelioxys (Platycoelioxys), MITCHELL, 1973

COELIOXYS (PLATYCOELIOXYS) MITCHELL, 1973

Type species: Coelioxys alatiformis Friese, 1921 .

Diagnosis: This monotypic subgenus can be distinguished from all other Coelioxys subgenera by the shape of S 5 in females, which is spatulate and greatly expanded towards the apex, its margins somewhat swollen and shining, and ventral surface convex ( Fig. 44 View Figures 44 and 45 ), and by the postgradular areas of T 2 – T 3 in males that are foveate in a manner not found in other subgenera (Fig. 45): on T 2, the fovea is elliptical and covered with minute whitish hairs, whereas in T 3 it is smaller and circular (Fig. 45). In females from other subgenera the S5 is elongate towards apex, never spatulate nor greatly expanded, except in C. (Paracoelioxys) alata , in which the S5 margins are greatly expanded but straight, never swollen, as in C. alatiformis ( Fig. 44 View Figures 44 and 45 ); the ventral surface of S5 is concave and the apex is broad and truncate, in contrast to the convex surface and ellipsoid apex in C. alatiformis . The fovea on the postgradular area of T 2 of males from other subgenera is never elliptical, hairy and deep, but slender as in C. conoidea ( Fig. 90 View Figures 87–90 ), C. rufescens , C. (Paracoelioxys) ( Fig. 88 View Figures 87–90 ), and C. (Boreocoelioxys) ( Fig. 27 View Figures 26–29 ); minute and circular, as in C. (Glyptocoelioxys) ( Fig. 78 View Figures 77–80 ), except C. chilensis [see Discussion of C. (Glyptocoelioxys)], and circular and bare, as in C. reginae , C. albolineata , and C. confusa .

Comments: This subgenus comprises only one species, C. alatiformis , which ranges from Mexico to Argentina ( Rocha-Filho & Packer, 2015).