medius, Acipenser Heckel [J. J.] in Fitzinger & Heckel 1836:293 [Annalen des Wiener Museums der Naturgeschichte v. 1 (no. 12); ref. 2077] Name in the synonymy of Acipenser schypa, not available; also appeared in later literature. •Questionably in the synonymy of Acipenser gueldenstaedtii Brandt & Ratzeburg 1833 -- (Kottelat 1997:30 [ref. 22952]). •Questionably in the synonymy of Huso gueldenstaedtii (Brandt & Ratzeburg 1833). Nomen Nudum. Current status: Synonym of Huso gueldenstaedtii (Brandt & Ratzeburg 1833). Acipenseridae. Habitat: freshwater, brackish, marine.