About Ophisurus serpens (Linnaeus, 1758)
Ophisurus serpens, commonly called the serpent eel, is an elongated, slender fish. It can reach a maximum total length of 250 cm (100 in) with a maximum diameter of 5 cm (2 in), while a more common total length is 100 cm (40 in). This species has a long, tapering snout where the upper jaw is longer than the lower jaw. Its teeth are sharply pointed and usually visible. The front nostril sits halfway between the snout tip and the eye, and the hind nostril is protected by a valve and hidden in a groove positioned closer to the eye. The gape extends all the way back to the eye, which has an almond-shaped pupil during the day and a circular pupil at night. The branchial opening is small, and is located just in front of the short pectoral fins. Both the dorsal fin and anal fin are long and low, and they begin well behind the pectoral fins. There are no pelvic fins or tail fin, and the lateral line is clearly visible. The serpent eel’s general body colour is pale brownish-green, with dark markings on the snout, often silvery reflections on the flanks, and a pale belly. Juvenile serpent eels have a less elongated snout and are solid silvery in colour. This eel is found in the eastern Atlantic Ocean, with a range stretching from Senegal to Portugal, as well as throughout the Mediterranean Sea. It has also been recorded from other sections of the African coast, the Indian Ocean, Australia, and New Zealand. This disjunct distribution may mean that two similar-looking separate species are actually involved. The serpent eel lives in soft muddy and sandy sediments, mostly on the continental shelf, at depths down to around 300 m (1,000 ft).
