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:

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

Cladogram from 2019 Massonne et al. study:

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

Cladogram from 2020 Cossette & Brochu study:

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

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