As is the case with many
fossil vertebrates discovered by 19th century paleontologists, the
taxonomy of
Protosphyraena has had a confusing history.
Fossil pectoral spines belonging to this taxon were first recognized in 1822, from chalk deposits in
England, by
Gideon Mantell, the physician and
geologist who also discovered the
dinosaur Iguanodon. In 1857, the fish was named
Protosphyraena ferox by the renowned
American naturalist and
paleontologist,
Joseph Leidy, based on Mantell's English finds. Earlier, Leidy had published an illustration of a
Protosphyraena tooth from the Cretaceous-aged Navesink Formation of
New Jersey (Maastrichtian), but mistakenly identified it as having come from a dinosaur. During the 1870s, B. F. Mudge, a fossil collector supplying material to rival paleontologists
Edward Drinker Cope and
Othniel Charles Marsh, discovered a number of specimens of
Protosphyraena in Niobrara exposures in Rooks and Ellis counties in
Kansas and sent them back east. Between 1873 and 1877, Cope renamed three species based on Mudge's specimens, all of which would eventually be recognized as belonging to the genus
Protosphyraena:
Erisichte nitida,
"Portheus" gladius, and
"Pelecopterus" pernicciosus. Between 1895 and 1903, paleontologists in America and England, including
Arthur Smith Woodward (1895), Loomis (1900), O. P. Hay (1903), in a series of important works, reviewed the genus, adding much to our understanding of this fish. Today, two species of
Protosphyraena are recognized from the Niobrara Chalk of the western
United States:
P. nitida and
P. perniciosa. An additional species,
P. bentonianum was named by Albin Stewart in 1898, based on a specimen from the older Lincoln Member of the Greenhorn Limestone (Upper
Cenomanian). Perhaps the oldest remains of
Protosphyraena in
North America have come from the upper beds of the Dakota Sandstone (middle
Cenomanian) in Russell County, Kansas (Everhart, 2005; p. 91). The species
Australopachycormus hurleyi (meaning "southern
Pachycormus" and named after Tom Hurley, who discovered the
holotype specimen) was a long-billed pachycormid from the
Albian of
Queensland, Australia, that was noted to be the earliest Cretaceous pachycormid from the Southern Hemisphere. It was already noted to closely resemble
Protosphyraena during its description. Later studies have found
Australopachycormus to be indistinguishable from
Protosphyraena, and they have thus been synonymized. The presence of
Protosphyraena in Australia suggests that it had already achieved a very wide global distribution early on in its evolutionary history. ==Anatomy==