Lewis Short
chĕlȳdrus (noun M) = χέλυδρος:
* A fetid serpent, living, for the most part, in water, Cels. 5, 27, 8; Verg. G. 3, 415; Ov. M. 7, 272; Luc. 9, 710; Sil. 3, 316; 8, 496; Prud. c. Symm. 1, 130.
Charlton T. Lewis, Charles Short, A Latin Dictionary