appendix, Petromyzon DeKay [J. E.] 1842:381, Pl. 64 (fig. 211) [Zoology of New-York; ref. 1098] Providence, Rhode Island; Hudson River, U.S.A. Syntypes: apparently lost. •Valid as Lampetra appendix (DeKay 1842) -- (Lee et al. 1980:23 [ref. 22416], Smith 1986:38 [ref. 22186], Robison & Buchanan 1988:74 [ref. 23393], Page & Burr 1991:22 [ref. 18983], Boschung 1992:18 [ref. 23239], Etnier & Starnes 1993:96 [ref. 22809], Jenkins & Burkhead 1994:175 [ref. 21581], Stauffer et al. 1995:28 [ref. 23376], Mettee et al. 1996:73 [ref. 25836], Lyons et al. 2000:20 [ref. 26594], Nelson et al. 2004:48 [ref. 27807], Bailey et al. 2004:59 [ref. 27882], Boschung & Mayden 2004:94 [ref. 27995], Scharpf 2005:5 [ref. 28940]). •Synonym of Lampetra lamottenii (Lesueur 1827) -- (Scott & Crossman 1998:64 [ref. 24570] as lamottei). •Valid as Lampetra appendix (DeKay 1842), subspecies appendix (DeKay 1842) -- (Fuller et al. 1999:19 [ref. 25838]). •Valid as Lethenteron appendix (DeKay 1842) -- (Lang et al. 2009:48 [ref. 31599], Page & Burr 2011:129 [ref. 31215], Renaud 2011:68 [ref. 31770], Page et al. 2013:48 [ref. 32708], Mateus et al. 2013:46 [ref. 32714], Naseka & Renaud 2020:53 [ref. 37921], Page et al. 2023:36 [ref. 40505]). Current status: Valid as Lethenteron appendix (DeKay 1842). Petromyzontidae. Distribution: North America: southeastern Canada and eastern U.S.A. Habitat: freshwater.