Esox lucius

E. lucius has an elongated body which is green to brown on the dorsal surface with lighter flanks bearing whitish spots. The dorsal fin origin is slightly in front of the anal origin and both fins are placed well back to allow for rapid acceleration (Hubbs and Lagler, 2004);the pectoral fins low on the body, based under the opercle with the pelvic fins, which are rounded and paddle-shaped, also low on the body. There are 17-25 dorsal rays, 10-22 anal rays, 19 caudal rays and 57-65 vertebrae. The duckbill-shaped head of E. lucius accounts for 25-30% of an average total length of 46-76 cm (Scott and Crossman, 1973). On the underside of each side of the lower jaw, there are five sensory pores. The body and most of the head are covered with small cycloid scales. The eyes are yellow and highly mobile (Lefevre, 1999).