P. bransoni P. bransoni is the
type species of
Paleorhinus. It was first described and named by
Samuel Wendell Williston in
1904 on the basis of the
holotype FMNH UC 632, a complete but fragmentary
skull that has been extensively reconstructed with plaster. It was collected at Squaw Creek of
Fremont County, Wyoming, from the
Carnian-aged
Popo Agie Formation of the Chugwater Group. The holotype was thoroughly described by Lees (1907). Hunt and Lucas (1991) referred
PPM P217 to
P. bransoni. It is an incomplete skull that was collected at Palo Duro Canyon,
Randall County, west Texas, from the Carnian-aged Camp Springs Member of the
Tecovas Formation. Later, Long and Murry (1995) referred additional material, including isolated
postcranial remains, to
P. bransoni from the Carnian-aged
Cooper Canyon Formation of the Dockum Group,
Howard County, Texas. TMM 31025-172, a complete skull, was collected at Otis Chalk Quarry 1 (also known as SMU 122), TMM 31100-8, 101, 175, 418, 419, 453 were collected at Otis Chalk Quarry 3, and TMM 31185-11, 38 were collected at Otis Chalk Quarry 3A.
P. angustifrons P. angustifrons was first described and named by
Oskar Kuhn in
1936 as a species of
Francosuchus.
P. angustifrons is known exclusively from the
holotype BSPG 1931 X 502 a partial skull lacking the
rostrum and
mandibles. It was collected at Ebrach Quarry, bed number 9 of
Bavaria, southern Germany, from the late
Carnian-aged
Blasensandstein Member of the Hassberge Formation. Hunt and Lucas (1991) mistakenly referred to
F. angustifrons as
Ebrachosuchus angustifrons, and considered it and the other two
Francosuchus species,
F. broilii and
F. latus, to be
synonyms of
Paleorhinus neukami.
"Z." arenaceus was suggested to represent the oldest reliably dated phytosaur, and was reassigned to various phytosaur species over the years, including
Belodon,
Mystriosuchus and
Phytosaurus. Although Hungerbühler (2001) redescribed
"Z." arenaceus as not belonging to Phytosauria and referred it to
Archosauria incertae sedis, Dzik & Sulej (2007) noted that its holotype "does not differ significantly from corresponding parts of the juvenile Krasiejów
Paleorhinus, which is clearly a phytosaur". Furthermore, as the Feuerbacher Heide Schilfsandstein, from which
"Z." arenaceus was collected, and Krasiejów share species of
Metoposaurus, it might be possible that they also share the same species of phytosaur. Even though they agreed that due to the very fragmentary nature of
"Z." arenaceus holotype the Krasiejów
Paleorhinus can't be referred to it, they tentatively used the name
Paleorhinus cf. arenaceus for the Krasiejów
Paleorhinus. and Wastphal (1976) referred these species, as well as,
E. neukami and
P. angustifrons to
Paleorhinus subgenus
Francosuchus, while Chatterjee (1978) placed the four species in
Francosuchus in a different subfamily. Hunt and Lucas (1991) considered these species to be synonymous with
Paleorhinus neukami. now referable to
Tetrapoda incertae sedis. •
"Paleorhinus" parvus Mehl, 1928 - Hunt and Lucas (1991) considered this species to be
synonymous with
P. bransoni, •
Parasuchus hislopi Lydekker, 1885 -
P. hislopi was based on a chimeric
syntype material - a
rhynchosaurian
basicranium mixed with
phytosaurian partial snout, scutes and some teeth.
Friedrich von Huene (1940) identified the basicranium as belonging to
Paradapedon huxleyi (now known as
Hyperodapedon huxleyi), thus he assigned the phytosaurian material to a newly named species "aff."
Brachysuchus maleriensis. Later,
Edwin Harris Colbert (1958) designated all the Indian parasuchian material as
Phytosaurus maleriensis. Gregory (1962) accepted this proposal.
Sankar Chatterjee (1978), who described many complete remains of the Indian parasuchian, showed that it is not assignable either to
Brachysuchus (which is closely related to or synonymous with
Angistorhinus), or to
Phytosaurus (a
doubtful name, probably the
senior synonym of
Nicrosaurus). He noted that since the rhynchosaur basicranium is neither the
holotype of
P. hislopi, nor the
lectotype of
Paradapedon huxleyi, the suppression of
P. hislopi should be avoided. Nevertheless, Hunt and Lucas (1991) considered the species to be a
nomen dubium, and provisionally created the combination
Paleorhinus hislopi for the diagnosable phytosaur specimens from the
Lower Maleri Formation, stating that the Indian species can be distinguished from other
Paleorhinus species. As a result, most subsequent studies referred all
Paleorhinus species to
Parasuchus in accordance with the rules of the
ICZN, while others kept referring
P. hislopi to
Paleorhinus. In light of the complex taxonomic history of
Paleorhinus, studies as of 2013 considered the synonymy between the genera to be premature. •
Promystriosuchus ehlersi Case, 1922 - Gregory (1962) and Hunt and Lucas (1991) referred this taxon to
Paleorhinus on the genus level, and considered it to be a
nomen dubium on the species level, due to the poor preservation of it holotype and only known specimen. Stocker and Butler (2013) suggested that
P. ehlersi may not be referable to
Paleorhinus and referred it to
Phytosauria incertae sedis.
Phylogeny The following
cladogram, from Kammerer et al., 2016, shows the relationships of
P. bransoni,
P. angustifrons, and
"P." sawini to other phytosaurs. The authors placed
P. bransoni and
P. angustifrons into the genus
Parasuchus, owing to their close relationship with
Parasuchus hislopi. {{clade|{{clade ==References==