Chiasmodontidae
The Chiasmodontidae, snaketooth fishes or swallowers, are a family of deep-sea predatory ray-finned fishes, part of the order Scombriformes, that are found in all oceans.
As suggested by their common name, they are characterized by their ability to engulf prey larger than themselves, due to their highly distensible stomachs.
Taxonomy
They are closely related to tunas & mackerels, with both families belonging to the suborder Scombroidei. They were formerly placed in the paraphyletic group "Trachinoidei".Genera
The following genera are known:Chiasmodon Johnson, 1864Dysalotus MacGilchrist, 1905Kali Lloyd, 1909Pseudoscopelus Lütken, 1892In addition, the extinct fossil genus †Bannikovichthys Carnevale, 2007 is known from the Middle Miocene of Italy. This genus appears to be more basal than the extant genera. Another species that was previously assigned to this family, "Pseudoscopelus grossheimi" from the Early Oligocene, is now known to be an early crocodile toothfish, Champsodon grossheimi Daniltshenko, 1960.