Crocodile shark

Description

The crocodile shark has a spindle-shaped body with a short head and a bulbous,pointed snout.The eyes are very large and lack nictating membranes (protective third eyelids).The five pairs of gill slits are long,extending onto the dorsal surface.The sizable,arched jaws can be protruded almost to the tip of the snout and contain large teeth,shaped like spikes in the front and knives on the sides.There are fewer than 30 tooth rows in either jaw;in the upper jaw,the first two large teeth are separated from the lateral teeth by a row of small intermediate teeth.The pectoral fins are small,broad,and rounded.The pelvic fins are nearly as large as the pectorals.The first dorsal fin is small,low and angular;the second dorsal fin is smaller than the first but larger than the anal fin.The caudal fin is asymmetrical with a moderately long upper lobe.The caudal peduncle is slightly compressed with weak lateral keels.The dermal denticles are small,with a flattened crown bearing small ridges and backward-pointing cusps It is dark brown above and paler below,sometimes with a few dark blotches on the sides and belly and/or a white blotch between the corner of the mouth and the first gill slit.The fins have thin translucent to white margins.The crocodile shark grows to a maximum length of 1.1 m (3.6 ft).Most individuals are 1 m (3 ft) long and weigh 4–6 kg (9–13 lbs).