Named By: Louis Agassiz.
Synonyms: Dirrhizodon, Heterogalaeus.
Classification: Chordata, Chondrichthyes, Elasmobranchii, Carcharhiniformes, Hemigaleidae.
Species: H. serra, H. curvatus, H. wyattdurhami, H. elongata.
Size: Largest living species up to 2.4 meters long, largest H. serra specimens estimated to be about 7 meters long.
Known locations: Worldwide.
Time period: Oligocene to Miocene.
Fossil representation: Teeth.
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 particularly large
species of Hemipristis, with the size of the
teeth and jaw
reconstructions of H. serra being roughly three
times larger than the
modern species H. elongata. Ergo, if the bite
of a large H.
serra was three times larger than a big H.
elongata, then it is
within the realms of possibility that a large H. serra
would also be
three times as long as a large H. elongata.
With a large H.
elongata measuring about two hundred and forty centimetres
this would make a large H. serra a little over
seven meters long,
bigger than the largest recorded great white shark. In all
seriousness though this is not that much a stretch of the imagination,
as H. serra was swimming in the oceans at the
same time as even
bigger sharks such as C.
chubutensis, and of
course the mighty C.
Hemipristis sharks are noted for having slim pointed teeth in their lower jaws and having broader triangular teeth in the upper jaws. Although this may seem curious it is actually a simple arrangement that allows the lower teeth to pierce the flesh of prey and holding it in place while the upper teeth saw through with their serrations. This allows Hemipristis to remove bite sized chunks from the bodies of large prey. The large size of H. serra meant that it could prey upon larger animals, a statement that is corroborated by the presence of Hemipristis tooth marks upon the bones of mammalian sirenians such as manatees.
Hemipristis serra teeth are very popular collectors’ items on the fossil market due to their colouration which makes them quite unique when compared with the teeth of other shark species.
- Quantifying a possible Miocene Phyletic change in Hemipristis (chondrichthyes) teeth. - Palaeontologia Electronica. - Richard E. Chandler, Karen E. Chiswell, and Gary D. Faulkner - 2006.