Rebellatrix divaricerca ("rebel coelacanth (with a) forked tail", after the unique tail fin) is a large prehistoric coelacanth from the Lower Triassic Sulphur Mountain formation and Wapiti Lake Provincial Park of British Columbia.

R. divaricerca's most distinguishing feature was its tuna-like forked tail (unusual for an actinistian fish), which suggested a fast-swimming and active lifestyle, unlike coelacanths related to the living species.

[2] PRPRC 2006.10.001, the holotype specimen, is a nearly complete fossil, with the exception of some fins and a large amount of the skull, as well as an incomplete tail fin.

Rebellatrix is believed to have been a fast-swimming predator, since its tail is clearly built for speed, and modern coelacanths only use the tail fin when attacking prey, and would have been one of the first non-sharks to fill this niche.

You can help Wikipedia by expanding it.This article about a Triassic fish is a stub.