In Depth Cladoselache is often hailed as the first true shark form to enter the fossil record, and although Cladoselache has a number of features that are different to the sharks that we know today, you can still see a basic fusiform body plan. One thing that makes Cladoselache stand out however is the lack … Read more
In Depth Helicoprion is one of the stranger ‘sharks‘ in the fossil record, although at the time that Helicoprion swam the oceans there were actually many sharks that did not conform to the ‘standard’ form that we know today. The majority of the remains of this shark are the teeth which are fossilised in a … Read more
In Depth Sclerorhynchus was in essence an ancient sawfish. The snout was long and specialised teeth projected out from the sides. This snout was probably the primary feeding aid in uncovering buried invertebrates like shell fish which could then be eaten by the mouth which was on the underside of the head. There has been … Read more
In Depth Hemipristis is a genus of weasel shark which includes the extinct species H. serra, H. curvatus and H. wyattdurhami, although the most popular species by far is H. serra. The last surviving member of the Hemipristis genus is H. elongata, better known as the Snaggletooth shark. H. serra seems to have been a … Read more
In Depth Palaeocarcharodon seems to have been one of the principal shark genera that appeared in the oceans after the Cretaceous that were now devoid of large marine reptiles. Palaeocarcharodon is often considered to be related to the large Cretaceous shark Cretoxyrhina, however it is the relationship to Carcharodon carcharias (the great white shark) and … Read more
In Depth Ptychodus was one of the most specialist sharks of the late Cretaceous oceans, as the teeth are adapted for crushing shells rather than tearing through flesh. As such the teeth are rounded rather than being triangular and pointed, and have a series of ridges that run across the surface of the crown. These … Read more
In Depth Duffinselache is an extinct genus of shark that is known to have swum in the waters around what is now England during the late Triassic. Further Reading - New Triassic stem selachimorphs (Chondrichthyes, Elasmobranchii) and their bearing on the evolution of dental enameloid in Neoselachii. - Journal of Vertebrate Paleontology 32 (2): 255–266. … Read more
In Depth Though only small, Echinochimaera is still a very interesting fish that is known to have swum in the waters of what is now Montana during the Carboniferous. Echinochimaera had a deep round body that was propelled by a relatively thin tail which ended in a small caudal fin. This indicates that Echinochimaera was … Read more
In Depth A cartilaginous fish and therefore relative of sharks and rays, Deltoptychius is often seen as an early rat tail. For a modern analogy, Deltoptychius would be a more primitive version of a modern Chimaera monstrosa. These kinds of fish are usually deep water species that swim around in virtual darkness as very little … Read more
In Depth Nine times out of ten Ischyodus in simply referred to as a prehistoric Chimaera. In this instance it is meant as being similar to Chimaera monstrosa, also known as the rat fish and the rabbit fish, due to its physical similarity. Both Ischyodus and Chimaera monstrosa are members of the Chondrichthyes, which means … Read more