SAND-EEL, or Sand-Launce. The fishes known under these names form a small family (Amrmodytidae) now included with the Scombresocidae in the sub-order Percesoces. They were formerly placed in the Anacanthini and supposed to be allied to the Gadidae, but a fossil form Cobitopsis has recently been described in which the pelvic fins are present, and are abdominal in position as in Belone and Scombresox.
Their body is of an elongate-cylindrical shape, with the head terminating in a long conical snout, the projecting lower jaw forming the pointed end. A low long dorsal fin, in which no distinction between spines and rays can be observed, occupies nearly the whole length of the back, and a long anal, composed of similar short and delicate rays, commences immediately behind the vent, which is placed about midway between the head and caudal fin. The caudal is forked and the pectorals are short. The total absence of ventral fins indicates the burrowing habits of these fishes. The scales, when present, are very small; but generally the development of scales has only proceeded to the formation of oblique folds of the integuments. The eyes are lateral and of moderate size; the dentition is quite rudimentary.
Sand-eels are small littoral marine fishes, only one species attaining a length of 18 in. (Ammodytes lanceolatus). They live in shoals at various depths on a sandy bottom, and bury themselves in the sand on the slightest alarm. Other shoals live in deeper water. When they are surprised by fish of prey or porpoises they are frequently driven to the surface in such dense masses that numbers of them can be scooped out of the water with a bucket or hand-net. Sand-eels destroy a great quantity of fry and other small creatures, such as the lancelet (Amphioxus), which lives in similar localities. They are excellent eating, and are much sought after for bait. They are captured by small meshed seines, as well as by digging in the sand. The eggs of sand-eels are small, heavier than sea-water and slightly adhesive: they are scattered among the grains of sand in which the fishes live, and the larvae and young at various stages of growth may be taken with the row-net in sandy bays in summer.
Sand-eels are common in the N. Atlantic; a species scarcely distinct from the European common sand-launce occurs on the Pacific side of N. America, another on the E. coast of S. Africa. On the British coasts three species are found: the greater sand-eel (Ammodytes lanceolatus), distinguished by a tooth-like bicuspid prominence on the vomer; the common sand-launce (A. tobianus), from 5 to 7 in. long, with unarmed vomer, even dorsal fin, and with the integuments folded; and the southern sand-launce (A. siculis), with unarmed vomer, smooth skin, and with the margins of the dorsal and anal fins undulated. The last species is common in the Mediterranean, but local, farther N. It has been found near the Shetlands at depths from 80 to 100 fathoms.