Halosaur
Halosaurs are eel-shaped fishes found only at great ocean depths. As the family Halosauridae, halosaurs are one of two families within the order Notacanthiformes; the other being the deep-sea spiny eels. Halosaurs are thought to have a worldwide distribution, with some seventeen species in three genera represented. Only a handful of specimens have been observed alive, all via chance encounters with remotely operated submersibles. The term "halosaur" refers to the type genus, Halosaurus, which is a Greek compound word, hals meaning "sea" and sauros meaning "lizard". Halosaurs have a spotty fossil record, the oldest known genus being Echidnocephalus from the Late Cretaceous strata of Westphalia, Germany, and the second oldest known genus, Laytonia, from Miocene strata of California and Oregon. The fossil specimens already bear strong resemblance to the modern genera. The halosaurs' greatly elongated bodies end in a whip-like tail; their scales are large. There is one small dorsal fin close to the sharply pointed, mostly scaleless head. The tail fin is greatly reduced, with the anal fin being the largest fin. Their pectoral fins are slender and also greatly elongated. The mouth is somewhat large, with the lower jaw shorter than the upper jaw. The gas bladder is absent.
Halosaur
Halosaur
Halosaur
Halosaur
Halosaur
Halosaur
Halosaur
Halosaur
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