Sawfish Genova

Sawfish, also known as carpenter sharks, are a family of rays characterized by a long, narrow, flattened rostrum, or nose extension, lined with sharp transverse teeth, arranged in a way that resembles a saw. They are among the largest fish with some species reaching lengths of about . They are found worldwide in tropical and subtropical regions in coastal marine and brackish estuarine waters, as well as freshwater rivers and lakes. They are endangered.

They should not be confused with sawsharks (order Pristiophoriformes) or the extinct sclerorhynchoids (order Rajiformes) which have a similar appearance, or swordfish (family Xiphiidae) which have a similar name but a very different appearance.

Sawfishes are relatively slow breeders and the females give birth to live young. They feed on fish and invertebrates that are detected and captured with the use of their saw. They are generally harmless to humans, but can inflict serious injuries with the saw when captured and defending themselves.

Sawfish have been known and hunted for thousands of years, and play an important mythological and spiritual role in many societies around the world.

Once common, sawfish have experienced a drastic decline in recent decades, and the only remaining strongholds are in Northern Australia and Florida, United States. The five species are rated as Endangered or Critically Endangered by the IUCN. They are hunted for their fins (shark fin soup), use of parts as traditional medicine, their teeth and saw. They also face habitat loss. Sawfish have been listed by CITES since 2007, restricting international trade in them and their parts. They are protected in Australia, the United States and several other countries, meaning that sawfish caught by accident have to be released and violations can be punished with hefty fines.

Taxonomy and etymology

The scientific names of the sawfish family Pristidae and its type genus '' Pristis'' are derived from the grc, πρίστης, prístēs, saw, sawyer.

Despite their appearance, sawfish are rays (superorder Batoidea). The sawfish family has traditionally been considered the sole living member of the order Pristiformes, but recent authorities have generally subsumed it into Rhinopristiformes, an order that now includes the sawfish family, as well as families containing guitarfish, wedgefish, banjo rays and the like. Sawfish quite resemble guitarfish, except that the latter group lacks a saw, and their common ancestor likely was similar to guitarfish.

Living species

The species level taxonomy in the sawfish family has historically caused considerable confusion and was often described as chaotic. Only in 2013 was it firmly established that there are five living species in two genera.

''Anoxypristis'' contains a single living species that historically was included in ''Pristis'', but the two genera are morphologically and genetically highly distinct. Today ''Pristis'' contains four living, valid species divided into two species groups. Three species are in the smalltooth group, and there is only a single in the largetooth group. Three poorly defined species were formerly recognized in the largetooth group, but in 2013 it was shown that ''P. pristis'', ''P. microdon'' and ''P. perotteti'' do not differ in morphology or genetics. As a consequence, recent authorities treat ''P. microdon'' and ''P. perotteti'' as junior synonyms of ''P. pristis''.

Extinct (fossil) species

In addition to the living sawfish, there are several extinct species that only are known from fossil remains. The oldest known is the monotypic genus '' Peyeria'' whose remains date back 100 million years, from the Cenomanian age (Late Cretaceous), though it may represent a rhinid rather than a sawfish. Indisputable sawfish genera emerged in the Cenozoic age about 60 million years ago, relatively soon after the Cretaceous–Paleogene mass extinction. Among these are ''Propristis'', a monotypic genus only known from fossil re