Lithosmylidia Riek, 1955

(Fig. 5)

Type species. Lithosmylidia lineata Riek, 1955: 678 (by original designation).

Diagnosis. Forewing medium sized; trichosors present; crossveins poorly preserved in wings of all specimens; costal area with veinlets widely spaced, mostly simple; subcostal area with sc-r crossveins not detected; crossveins in area between RA and RP few or absent (one detected in one specimen of L. parvula); RP originating close to wing base, with at least 10 branches, very slightly sinuous distally in some species; crossveins of RP field not well preserved in most material, but apparently restricted to a few random ones proximally and two widely separate and irregular gradate series; M forked close to wing base; CuA irregularly pectinate forked, with branches oblique. CuP dichotomously forked with few branches; 1A pectinate, length variable; 2A deeply forked; 3A short and apparently simple; HW unknown.

Comments. A specimen of L. lineata was considered by Riek (1955) as a hind wing, however Lambkin (1988) instead argued that it represented a forewing. Originally, Lithosmylidia was described by Riek (1955) belonging to Kempyninae, but Makarkin et al. (2014) argued that the genus belonged to Archeosmylidae . Characters such as Sc+RA joining the wing margin before the wing apex and the lack of RP crossveins support its placement in Archeosmylidae; unfortunately, important information about the hind wing cubital and anal vein fields were not preserved in any specimen.

Included species.

L. baronne Lambkin, 1988 (Australia) (Middle Triassic)

L. lineata Riek, 1955 (Australia) (Late Triassic)

L. parvula Riek, 1955 (Australia) (Late Triassic)