The new Actinopterygian order Guildayichthyiformes from the Lower Carboniferous of Montana (USA) Author Lund, Richard Department of Biology, Adelphi University, Garden City, New York 11530 (USA) lund @ panther. adelphi. edu text Geodiversitas 2000 22 2 171 206 journal article 10.5281/zenodo.4664626 1638-9395 4664626 Genus Discoserra n. gen. TYPE SPECIES . — Discoserra pectinodon n. gen. n. sp. by original designation. ETYMOLOGY. — Discoserra , serrated disc, descriptive of the appearance of the body in lateral view. DIAGNOSIS.—Teeth of the premaxilla,maxilla and dentary long, thin, and styliform. Posterior end of maxilla does not extend back to level of anterior margin of orbit. Parietals excluded from contact in dorsal midline by postrostral 2, which contacts supraoccipital. No transverse supratemporal commissure in supraoccipital. Two rows of paired bones over orbit. One to three interopercular bones; two to three small postspiraculars and a presupracleithrum. Branchiostegals very variable in size, number and shape. Dorsal ridge scales with small, forwardly facing hooks; two to three small anal fin hooks.Origin of anterior edge of dorsal fin set well below dorsal margin of ridge scales. All fins with well spaced rays; pelvic fin reduced, caudal fin rounded.