A prehistoric, enormous cartilaginous rat-fish belonging to the same family as sharks and rays, the Helicoprion existed for about 85 million years, from the end of the Carboniferous period till the Triassic, disappearing around 225 million years ago.
Helicoprion
Since cartilage doesn’t really fossilize, the bony tooth whorls are all that are found of the Helicoprion. And, for mor than a hundred years, scientists couldn't agree on where that tooth whorl would go on the animal, creating all sorts of wild interpretations. When we first made a Helicoprion shirt, we depicted it in the classic "whip-jaw" style, with its bottom jaw practically dangling below like a curled up tooth lined whip.
Wrong!
Finally in 2016, when we launched another Kickstarter campaign, we brought back an updated version of the beast with accurate jaw anatomy. Watch the video to the right to learn more!
Also the actual anatomy of the fish is a bit up for interpretation as well. Since the fish could reach 25 feet in length, it's hard to imagine it as a slow, awkward, modern day rat-fish. Was it more of a mackerel shark in shape, like a mako or a greatwhite, or more floppy like the goblin shark or sand tiger? Maybe it was more prehistoric in nature, like today's ancient looking Hexanchiformes, such as the sixgill and sevengill sharks, whom possess more than the usual five gills on each side of the head (hence the name) and only one dorsal fin? We can only guess. So, I took some liberties and mixed in a bit of the goblin shark, in regards to fin placement and the strange pointed nose, but gave it the extra long pectoral fins of a Blue Shark, and a caudal fin with a long upper lobe and sub-terminal notch, but with a highly exaggerated caudal keel. He got an extra gill too, for prehistoric sake.