The order Elopiformes includes two small families of medium to large-sized fishes found in coastal marine, estuarine and freshwater environments. Elopiformes have well-developed gular plates, or extra bones in the throat between the lower jaws, found only in some primitive bony fishes.
Recent molecular work has shown that the order Elopiformes is basal to other groups within the Subdivision Elopomorpha, which also contains the true eels (Order Anguilliformes) and the bonefishes (Order Albuliformes). Like their relatives, tarpons and tenpounders have a leptocephalus larval stage, that unlike most elopomorph fishes, has a forked caudal fin.
The elopiform fossil record dates back 135 million years ago to the Upper Cretaceous period, with fossils resembling tarpons.
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