Biology:Procaimanoidea

Short description: Extinct genus of reptiles

Procaimanoidea Temporal range: Eocene, 46.2–41.2 Ma PreЄ Є O S D C P T J K Pg N ↓
Fossil specimen of P. utahensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauromorpha
Clade:	Archosauriformes
Order:	Crocodilia
Family:	Alligatoridae
Subfamily:	Alligatorinae
Genus:	†Procaimanoidea Gilmore, 1946
Species
†P. utahensis Gilmore, 1946 (type) †P. kayi (Mook, 1941 [originally Hassiacosuchus kayi])

Procaimanoidea ("Before Caiman-forms") is an extinct genus of alligatorid from the Eocene of North America. It was named posthumously in 1946 by Charles W. Gilmore; the type species is P. utahensis, from the Uintan (middle Eocene) of Utah. It is based on USNM 15996, a nearly complete skull and partial left hind leg. A second species, P. kayi, was named in 1941 by C.C. Mook as a species of Hassiacosuchus, for remains from the Bridgerian (early Eocene) of Wyoming. It was reassigned to Procaimanoidea in 1967 by Wassersug and Hecht.

Description

Procaimanoidea was a small alligatorid, and slightly heterodont, the last four teeth on each side of the jaws having blunt tips.

Phylogeny

Recent studies have consistently resolved Procaimanoidea as a member of Alligatorinae, although its relative placement is disputed, as shown by the cladograms below.

Cladogram from 2018 Bona et al. study:

Alligatorinae

Ceratosuchus burdoshi†     Allognathosuchus polyodon†     Allognathosuchus wartheni†     Navajosuchus mooki†     Arambourgia gaudryi†       Procaimanoidea kayi†     Procaimanoidea utahensis†         Wannaganosuchus brachymanus†       Alligator prenasalis†       Alligator mcgrewi†       Alligator olseni†       Alligator sinensis Chinese alligator       Culebrasuchus mesoamericanus†       Alligator mississippiensis American alligator     Alligator mefferdi†     Alligator thomsoni†

Cladogram from 2019 Massonne et al. study:

Alligatorinae

Alligator prenasalis†     Alligator mcgrewi†           Alligator olseni†       Alligator sinensis Chinese alligator       Alligator thomsoni†     Alligator mefferdi†     Alligator mississippiensis American alligator               Procaimanoidea utahensis†     Procaimanoidea kayi†         Arambourgia gaudryi†       Hassiacosuchus haupti†       Wannaganosuchus brachymanus†       Allognathosuchus wartheni†     Allognathosuchus polyodon†

Cladogram from 2020 Cossette & Brochu study:

Alligatorinae

Ceratosuchus burdoshi†     Hassiacosuchus haupti†     Navajosuchus mooki†       Allognathosuchus polyodon†       Alligator mcgrewi†     Alligator prenasalis†         Wannaganosuchus brachymanus†         Arambourgia gaudryi†       Procaimanoidea kayi†     Procaimanoidea utahensis†           Alligator olseni†       Alligator sinensis Chinese alligator       Alligator mississippiensis American alligator     Alligator mefferdi†     Alligator thomsoni†

External links

• Procaimanoidea in the Paleobiology Database

Wikidata ☰ Q7247089 entry