Name: Enchodus
Time: Late Cretaceous to Paliocene
Locality: Worldwide
Size: 7 in / 18 cm long
Salmon and trout are surviviors of a second surge of evolutionary phase that took place at the very end of the Cretaceous and during the Early Tertiary. This stage in evolution led to the advanced bony fishes, and from their ancestors descended all the modern types of teleost.
Enchodus was one of these early, salmon-like teleosts. Its large head and big eyes, together with its lightweight, streamlined body, suggests an agile predator of the open seas. The scales were reduced to a bank along each flank; the pelvic fins were set well back on the belly, directly beneath the large, stabilizing dorsal fin; and the pectoral fins were mounted higher on the flanks, giving greater control of steering and braking.
The remarkable feature of Enchodus however, was its mouthful of greatly elongated teeth. They were slightly recurved and interlocked when the jaws were closed, to form an effective trap. Enchodus probably preyed on plankton-eating fishes in the surface waters.
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