Sclerorhynchoidei is an extinct suborder of

rajiform Fish locomotion is the various types of animal locomotion used by fish, principally by swimming. This is achieved in different groups of fish by a variety of mechanisms of propulsion, most often by wave-like lateral flexions of the fish's bod ...

rays that had long

rostra The rostra ( it, Rostri, links=no) was a large platform built in the city of Rome that stood during the Roman Republic, republican and Roman Empire, imperial periods. Speakers would stand on the rostra and face the north side of the comitium tow ...

with large denticles similar to

sawfishes 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 wit ...

and

sawsharks A sawshark or saw shark is a member of a shark order (Pristiophoriformes ) bearing a unique long, saw-like rostrum (snout or bill) edged with sharp teeth, which they use to slash and disable their prey. There are eight species within the Pristio ...

. This feature was convergently evolved and their closest living relatives are actually skates. While they are often called "sawfishes", sawskates is a more accurate

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

for sclerorhynchoids. The suborder contains five named families:

Ganopristidae Ganopristidae is an extinct family of cartilaginous fish from the Cretaceous belonging to the suborder Sclerorhynchoidei. While the name Sclerorhynchidae is often used for this family, it is a junior synonym of Ganopristidae. This family contains ...

, Ischyrhizidae, Onchopristidae,

Ptychotrygonidae ''Ptychotrygon'' is a genus of sawfish-like Late Cretaceous ray whose fossils have been found worldwide. It, '' Ptychotrygonoides'', '' Texatrygon'', and '' Asflapristis'' are members of the family Ptychotrygonidae within the suborder Sclerorhyn ...

, and Schizorhizidae. Several genera (see below) are not currently placed in any of these families. Sclerorhynchoids first appeared in the

Barremian The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 129.4 ± 1.5 Ma ( million years ago) and 121.4 ± 1.0 Ma). It is a subdivision of the Early Cretaceous Epoch (or Lower Cretaceous Series). It is pre ...

and went extinct during the

Cretaceous–Paleogene extinction event The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction) was a sudden extinction event, mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million y ...

, with former

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...

occurrences being misidentifications or reworked specimens.

Phylogeny

Below is a cladogram of Sclerorhynchoidei, with the topology based on Villalobos-Segura ''et al.'' (2021b) and the family taxonomy based on Greenfield (2021).

Other genera

*†'' Agaleorhynchus'' *†'' Ankistrorhynchus'' *†'' Archingeayia'' *†''

Atlanticopristis ''Atlanticopristis'' (meaning "Atlantic saw") is an extinct genus of sclerorhynchid (a sawfish-like chondrichthyan) that lived during the Middle Cretaceous (Cenomanian) of what is now the Northeast Region of Brazil, between 100.5 and 93.9 mill ...

'' *†'' Australopristis'' *†''

Baharipristis ''Baharipristis'' is an extinct genus of sawfish-like shark from the Cretaceous period. It contains a singular species, ''B. bastetiae''. It was described from the Cenomanian-aged Bahariya formation of Gebel Ghorabi, Egypt Egypt ( ar, مص ...

'' *†'' Biropristis'' *†'' Borodinopristis'' *†'' Celtipristis'' *†'' Columbusia'' *†''

Ctenopristis ''Ctenopristis'' is a prehistoric genus of sawfish whose fossils are found in rocks dating from the Maastrichtian stage in Jordan. The anterior teeth of ''Ctenopristis'' have a high cusp compared to certain other ancient sawfish genera. See ...

'' *†''

Dalpiazia ''Dalpiazia'' is a prehistoric genus of sclerorhynchid sawfish whose fossils are found in rocks dating from the Maastrichtian stage in mines in Jordan and Syria, and in Morocco. The type species ''D. stromeri'' was named in honor of Ernst Stro ...

'' *†''

Harranahynchus ''Harranahynchus'' is an extinct genus of schizorhizid sclerorhynchoid that lived during the Late Cretaceous. It contains one valid species, ''Harranahynchus minutadens''. It is known from relatively complete cranial and body fossils found in ...

'' *†''

Iberotrygon ''Iberotrygon'' is an extinct genus of sclerorhynchiform ray from the Cenomanian Mosqueruela Formation of Spain. Only the single species ''I. plagiolophus'', is known; it was named and described in 2009. It is known from the holotype MPZ 2005 ...

'' *†'' Kiestus'' *†'' Marckgrafia'' *†'' Onchosaurus'' *†'' Plicatopristis'' *†''

Pucapristis ''Pucapristis'' is a prehistoric genus of sclerorhynchid ray whose fossils first appear in the fossil record in rocks dating from the Maastrichtian stage. The genus was described in 1963 by Schaeffer.Renpetia'' *† Sao Khua sclerorhynchoid

References

{{Taxonbar, from=Q25095431 Sclerorhynchoidei