World Register of Marine Species (WoRMS)
Ceratium gravidum var. praeolongum Lemmermann, 1899
Guiry, M.D. & Guiry, G.M. (2026). AlgaeBase. World-wide electronic publication, National University of Ireland, Galway (taxonomic information republished from AlgaeBase with permission of M.D. Guiry). Ceratium gravidum var. praeolongum Lemmermann, 1899. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=696053 on 2026-08-27
Lemmermann, E. (1899). Ergebnisse einer Reise nach dem Pacific. (H. Schauinsland 1896\/97). Abhandlungen herausgegeben vom Naturwissenschaftlichen zu Bremen, 16: 313-398, pls I-III.