Species: sternbergii (GILMORE, 1911) BROCHU, 1997
Etymology:
= Leidyosuchus sternbergii GILMORE 1911

Holotype: USNM 6533

Locality: North side of Cheyenne River, Converse County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Skull, lower jaw, 8 vertebrae, both humeri, the right fibula, left metatarsal II, and other fragmentary parts of the skeleton.

Referred material:

AMNH 5898: Skull.

 

BYRANT, 1990

Locality: Northeastern Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UCMP 130767: Dentary and angular fragments.

 

Locality: Northeastern Montana.

Horizon: Tullock Formation.

Biostratigraphy:

Age: Early Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material:

UCMP 126099, 130469: Skulls.

UCMP 119282: Anterior snout.

UCMP 120434: Snout and jaws.

UCMP 130435: Skull fragments and jaws.

 

ESTES, 1964

Locality: Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

Number: Not given: Skull fragments, teeth, vertebrae, limb bones and scutes.

 

ESTES & BERBERIN, 1970

Locality: Bug Creek Anthills, McCone County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

MCZ 3648: Teeth

 

BREITHAUPT, 1982

Locality: UW Locality V-79032, Rock Springs Uplift, Sweetwater County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UW 14077, 14078, 14079: Teeth.

UW 14080: Parietal Fragment.

 

CARPENTER, 1979

Locality: Weld County, Colorado.

Horizon: Laramie Formation.

Biostratigraphy:

Age: Lancian Age, upper Maastrichtian Stage, uppermost Senonian Subepoch, Upper Upper Gulf Epoch, Late Cretaceous.

Material:

UCM 38529: Teeth.

 

COULTON, 1975

Locality: West side of the Red Deer River near Morrin Bridge in Central Wheatland County, Alberta Province, Canada.

Horizon: Edmonton Formation.

Biostratigraphy:

Age: Edmontonian age, Upper Campanian Stage- Lower Maastrichtian Stage, Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

RLC 715: Tooth.

 

GILMORE, 1911

Locality: Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

Number: Not given: Incomplete skull.

 

HOLROYD & HUTCHISON, 2002

Locality: V 86064, western North Dakota.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian Age, upper Maastrichtian Stage, uppermost Senonian Subepoch, Upper Upper Gulf Epoch, Late Cretaceous.

Material:

131769:

 

Locality: V 86065, western North Dakota.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian Age, upper Maastrichtian Stage, uppermost Senonian Subepoch, Upper Upper Gulf Epoch, Late Cretaceous.

Material:

Number: Not given:

 

LESSNER, PETERMANN & LYSON, 2025

Locality: Corral Bluffs, east of Colorado Springs, El Paso County, Colorado.

Horizon: Denver Formation.

Biostratigraphy:

Age: Lower Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material:

DMNH EPV.60862: Incomplete caudals skull and fragmentary rostrum consistion of partial quadrates, quadratojugal, maxillae, frontal, parietal, prefrontals, postorbitals, pterygoid, laterosphenoids, prootics, exoccipital, supraoccipital, jugal, bassisphenoid, basioccipital and squamosals.

DMNH EPV.136252: Central region of skull consisting of prefrontals, lacrimals, vomer, palatines, basispheonoid, basioccipital, prootics, partial maxillae, nasals, parietal, jugals, ectopteryglids, frontal, postorbitals, squamosals, supraocciptital, pterygoids, laterospenoids, exocciptials and quadrates.

DMNH EPV.144434: Fragmentary skulls consisting of ectopterygoids, pterygoid, supraocciptial, exoccipitials, partal maxillae, palaitnes, right jugal, right lacrimal, quadrates, squamosals, basioccipital, quadratojugals, parietal, right detnary, angular, splenial, partial suqangular, left parietal splenial, angular, associated osteroderms, fragmetnary elemetns including left humerus and vertebra.

 

Locality: West Bijou study area, ~75 km to the north and east of teh Coral Bluffs studya area, Arapahoe and Elbert Counties, Colorado.

Horizon: Denver Formation.

Biostratigraphy:

Age: Lower Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material:

Note: authors states tentative referrals from Corral Bluffs and West Bijou:

UCM 123254: Isolated fragment of right maxilla.

UCM 110292: Isolated osteoderms.

UCM 63350: Isolated osteoderms.

DMNH EPV.143002: Poorly presrved fragmentary rostrum.

DMNH loc. 143024: Isoalted osteoderms and vertebra.

DMNH EPV.66785: Isoalted osteoderms.

DMNH EPV.67756: Isoalted osteoderms.

DMNH EPV.143025: Fragmetnary cranial material and osteoderms.

 

TRIEBOLD, 1997

Locality: Sandy Site, Harding County, South Dakota.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

Number: Not given:

 

WHITMORE, 1988

Locality: SDSM Locality V851, Zerbst Locality, east of the Cheyenne River, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

SDSM 12450: 98 isolated teeth.

 

Locality: SDSM Locality V852, Hanson Locality, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

SDSM 12449: 86 isolated teeth.

 

Locality: SDSM Locality V853, Leonard’s Lizard Site, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

SDSM 12448: 7 isolated teeth.

 

Locality: SDSM Locality V851A, Lower Zerbst Locality, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

SDSM 12447: 1 isolated tooth.

 

Locality: SDSM Locality V685, Greasewood Creek Locality, northern side of the south fork of the Greasewood Creek, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

SDSM 12711: 15 isolated teeth.

 

= Leidyosuchus gilmori MOOK, 1959
Etymology: In honor of Charles Gilmore.

Holotype: AMNH 5352

Locality: Red Deer River, 2 miles below Steveville, Dinosaur Provincial Park, Newell County, Alberta Province, Canada.

Horizon: Dinosaur Park Formation, upper Judith River Group.

Biostratigraphy:

Age: Judithian age, Middle Campanian Stage, middle Senonian subepoch, upper Gulf Epoch, Late Cretaceous.

Material: Incomplete, crushed skull with skull table, braincase and posteriorolateral portion of the left side reconstructed.

_____________________________________________________________________________________

Species: acutidentatus (STERNBERG, 1932) BROCHU, 1997
Etymology:
= Leidyosuchus acutidentatus STERNBERG, 1932

Holotype: NMC 8544

Locality: SE 1/4 Sec. 31, T. 5R. 28 W of 2 principal meridian, southeast Montague Lake, Saskatchewan Province, Canada.

Horizon: Upper Ravenscrag Formation.

Biostratigraphy:

Age: Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material: Skull and dentary.

Referred material:

LUCAS & SULLIVAN, 1986

Locality: MNA locality 325 in the SW 1/4, NE 1/4, NE 1/4, NW 1/4, sec. 29, T24N, R9W, Kimbeto Arroyo, San Juan County, New Mexico.

Horizon; Torrejonian interval of the Nacimiento Formation.

Biostratigraphy:

Age: Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material:

MNA P. 2612: Skull and lower jaw plus associated vertebrae and other postcrania.

_____________________________________________________________________________________
Species: wilsoni (MOOK, 1959) BROCHU, 1997
Etymology:
= Leidyosuchus wilsoni MOOK, 1959

Holotype: AMNH 7637

Locality: Near Wamsutter, Sweatwater County, Wyoming.

Horizon: Green River Formation, immediately above the Wamsutter Coal Beds.

Biostratigraphy:

Age: Middle Eocene Epoch, Paleogene Period, Lower Tertiary Subera, Lower Cenozoic Era.

Material: Skull missing some of the left premaxilla.

Referred material:

= Borealosuchus cf. B. wilsoni STOUT, 2012

Locality: La Brarge, Green River, Wyoming.

Horizon: Bridger Formation.

Biostratigraphy:

Age: Bridgerian, Early Eocene Epoch, Paleogene Period, Lower Tertiary Subera, Lower Cenozoic Era.

Material:

TATE 2070: Anterior left dentary with teeth.

 

= Diplocynodon stuckeri MOOK, 1960
Etymology:

Holotype: AMNH 6050

Locality: Leavitt Creek, near Fort Bridger, Wyoming.

Horizon: Bridger beds.

Biostratigraphy:

Age: Middle Eocene Epoch, Paleogene Period, Lower Tertiary Subera, Lower Cenozoic Era.

Material: Anterior portion of a left ramus of lower jaw.
_____________________________________________________________________________________

Species: riggsi (SCHMIDT, 1938) BROCHU, 1997
Etymology:
= Leidyosuchus riggsi SCHMIDT, 1938

Holotype: FMNH P15582

Locality: Plateau Valley Beds, Hell's Half Acre, Mesa County, Colorado.

Horizon: DeBeque Formation, Plateau Valley local fauna.

Biostratigraphy:

Age: Late Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material: Imperfect skull.

Paratype: FMNH P15778: Ramus fragment with 5 teeth.

_____________________________________________________________________________________
Species: formidabilis (ERICKSON, 1976) BROCHU, 1997
Etymology:
= Leidyosuchus formidabilis ERICKSON, 1976

Holotype: SMM P71.16.28

Locality: SMM Wannagan Creek Quarry, Lower Level, NW 1/4 Sec. 18. 18, T. 141 N., R. 102 W., Billings County., North Dakota.

Horizon: Bullion Creek Formation.

Biostratigraphy:

Age: Late Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material: Skull with lower jaw intact except for posterior part of left half.

Referred Material:

SMM P70.16.3: Radius.

SMM P70.16.21: Ischium.

SMM P70.20.9: Skull and lower jaw.

SMM P70.20.171: Femur.

SMM P72.34.184, P70.20.377, P70.20.388, P70.20.393, P70.20.412: Mandibles.

SMM P70.20.404: Ilium.

SMM P70.20.409: Coracoid.

SMM P71.16.10: Scapula.

SMM P71.16.17: Ulna.

SMM P71.16.106: Proatlas.

SMM P71.16.256: Pubis.

SMM P70.20.407, P71.16.29, P72.34.87, P72.34.183: Skulls and lower jaws.

SMM P72.34.95: Tarsus.

SMM P72.34.126: Branchial horn.

SMM P71.16.7, P71.16.24, P73.34.18, P72.34.150, P72.34.185: Ribs.

SMM P75.22.6, P72.34.202, P74.24.105: Skulls of a juveniles.

SMM P72.34.203: Humerus.

SMM P73.25.70: Juvenile vertebra.

SMM P74.24.6: Skull, lower jaw and skeleton.

SMM P74.24.36: Skeleton.

SMM P74.24.37: Interclavicle.

SMM P74.24.103: Skull.

SMM P74.24.185: Hatchling vertebra.

SMM P74.24.186: Young neurocentrum.

SAWYER & ERICKSON, 1998

Paleopathologies

SMM P84.19.3, P78.14.133: Skulls with perforating fractures.

SMM P79.19.1026: Left surangular with probable perforating fracture.

SMM P83.12.64: Atlas with possible osteomyelits missing intercentrum and neurocentra.

SMM P76.33.289: First dorsal with exostosis, probable chondroma.

SMM P75.22.518: Dorsal vertebra with peristeopathy.

SMM P.70.20.1775: Dorsal vertebra with periosteopathy.

SMM P.70.2-.1752, P72.34.96, P73.25.73, P74.24.6, P75.22.1-7, P75.22.110, P75.22.351, P76.28.474. P76.28.863, P76.28.936, P76.28.980, P76.28.1014, P76.33.392, P79.19.109, P79.19.772, P79.19.781, P79.19.782, P79.19.807, P79.19.816, P79.19.817, P79.19.900, P79.19.987, P79.19.990, P. 79.19.991, P79.19.992, P79.19.993, P79.19.1095, P80.10.344 (2 elements) P82.12.5, P83.12.99, P89.6.56, P89.6.161, P91.17.198, P91.17.201, P93.22.61, P93.22.146, P93.22.148, P93.22.168, P95.13.18, P95.13.19, P95.13.20, P95.13.21, P95.13.22, P95.13.23, P95.13.24, P95.13.25: Pathologic dorsal centra.

SMM P89.6.214: Dorsal vertebra with possible osteomelitis.

SMM P70.20.408: 3 dorsal vertebra with spondyloarthropathy.

SMM P82.12.258: First sacral vertebra missing neural spine, but includes left rib with periosteopathy.

SMM P.95.13.6: Caudal vertebra with transverse fracture and periosteopathy.

SMM P79.19.1001: Caudal vertebral centrum with periosteopathy.

SMM P71.16.293, P76.28.847, P76.33.284, P76.33.464, P79.19.649, P79.19,654, P79.19.665, P79.19.669, P79.19.678, P79.19.809, P79.19.859, P79.19.988, P79.19.999, P79.19.1000, P79.19.1002, P79.19.1089, P83.12.42, P91.17.105, P93.14.148, P93.22.98, P95.13.3, P95.13.4: Pathologic caudal centra.

SMM P72.34.24: Chevron with transverse fracture.

SMM P83.12.65: Chevron with probable transverse fracture.

SMM P79.19.997: Chevron with possible malformation.

SMM P83.12.63: Cervical rib with probable osteomyelitis.

SMM P73.25.115: Dorsal rib with possible greenstick fracture.

SMM P89.6.79: Dorsal rib with ribbed periosteopathy and spondyloarthropathy.

SMM P70.20.420: Interclavicle with probable depressed fracture.

SMM P76.28.804: Right scapula with exostosis.

SMM P95.13.12: Right humerus with periosteopathy.

SMM P74.24.12: Radius with fusiform osteopathy.

SMM P77.33.21: ¾ of proximal end of a radius with periosteopathy.

SMM P75.22.346: Radius missing distal end with probable comminuted fracture and secondary osteomyelitis.

SMM P76.28.905: ¾ shaft of a ulna missing both ends and having periosteopathy.

SMM P79.19.1007, P76.28.372: 2 ulnae with periostopathy.

SMM P75.22.480 : Left ulna with probable osteomylitits.

SMM P73.25.1 : Left pubis with ribbed periosteopathy.

SMM P77.33.7 : Right femur with possible oblique fracture.

SMM P76.28.900 : Left femur with osteomyelitis.

SMM P79.19.1120 : Proximal 2/3rds of a femur with exostoses.

SMM P70.20.1783 : Proximal ½ of femur with exostoses.

SMM P76.28.55: tibia with oblique fracture and probable secondary osteomyelitis.

SMM P72.34.240: Distal ½ of fibula with transverse fracture.

SMM P92.2.53: Metapodial with comminuted fracture.

SMM P70.20.77, P76.28.53, P76.28.374, P76.28.375, P79.19.1012, P95.13.8: 6 metapotals with probable transverse fractures.

SMM P70.21.242, P72.34.25, P76.10.9. P76.28.364, P76.28.369, P76.28.370, P76.28.886, P79.19.313, P79.19.1006, P79.19.1014: Metopodials with periostopathy.

SMM P71.16.248: Metopodial with fusiform osteopathy.

SMM P95.13.9: Metacarpal V with spondyloarthropathy.

SMM P76.28.3: Metatarsal/phalange with sponyloarthropathy.

SMM P73.25.118, P75.22.47, P75.22.55, P75.22.517, P76.28.10, P77.33.246, P79.19.1004, P95.13.10: Metaodials with spondyloarthropathy.

SMM P75.22.4: Phalange with transverse fracture.

SMM P95.13.26: Phalange with oblique fracture.

SMM P70.20.1716, P72.34.23, P73.25.116, P74.24.326, P76.28.363, P76.28.368, P76.28.861, P77.33.248, P77.33.249, P77.33.250, P79.19.543, P79.19.995, P79.19.1003: Phalanges with periosteopathy/osteopathy.

SMM P74.24.232. P76.28.362, P76.28.367, P76.28.371, P76.28.838, P76.28.951, P79.19.1008, P92.2.25, P93.22.23: Phalanges with spondyloarthropathy.

SMM P74.24.29: Phalange with exostosis.

SMM P70.20.74, P76.28.450, P95.13.17: Gastralia with probable transverse fractures.

SMM P70.20.92, P71.16.274, P74.24.67. P74.24.76, P74.24.87, P79.19.232. P79.19.241, P79.19.245, P79.19.247, P79.19.257, P79.19.1017, P79.20.280, P89.6.104, P91.17.156, P93.22.99, P93.22.106, P93.22.114, P95.13.15, P95.13.16: Gastralia with probable transverse fractures.

SMM P79.19.1005: ungual with spondyloarthropathy.

SMM P70.20.1692: Ungual with exostosis.

SMM P77.33.88: Osteoscute with two perforating fractures.

SMM P72.34.230: Osteoscute with perforating fracture.

SMM P70.20.105, P71.16.259, P72.34.237, P72.34.239, P74.24.424, P75.22.164, P76.33.441, P79.19.935, P79.19.936, P79.19.937, P79.19.949, P79.19.961, P79.19.962 (“buttonhole”), P79.19.964, P79.19.966, P79.19.976, P79.19.984, P82.12.373, P82.12.497, P83.12.83, P83.12.116: Osteoscutes with perforating fractures.

SMM P82.12.382: Osteoscute with periostepathy/osteopathy.

SMM P79.19.941: Osteoscute with periosteopahty/osteopathy.

SMM P79.19.955: Osteoscue with periostepathy/osteopathy.

SMM P71.16.261, P73.25.117, P74.24.494, P76.28.866, P76.33.414 (2 specimens found together), P76.33.439, P76.33.457, P79.19.934, P79.19.940, P79.19.943, P79.19.946, P79.19.953, P79.19.954, JP79.19.956, P79.19.963, P79.19.974, P79.19.981, P79.19.985, P82.12.263, P82.12.496, P89.6.117, P93.22.37, P93.22.186, P95.13.13: Osteoscutes with periostoeopathy/osteopathy.

SMM P82.12.306: Osteoscute with probable malformation.

SMM P82.12.419: Osteoscute with probable malformation.

_____________________________________________________________________________________

Species: griffithorum emend WU, BRINKMAN & FOX, 2001
Etymology: In honor of the Griffith family, the owner of the land from which the holotype specimen was collected.
= Borealosuchus griffithi WU, BRINKMAN & FOX, 2001

Holotype: UALVP 40955

Locality: Griffith’s Farm, SW ¼, S18, T34, R21, W4 (According to the Prairie township and range system), Red Deer River Valley, southern Alberta Province, Canada.

Horizon: Less than 1 m above Nevis (#13) Coal Seam, basal coaly portion of the Scollard Formation.

Biostratigraphy:

Age: Earliest Paleocene Epoch, Lower Paleogene Period, Lower Tertiary Subera, Cenozoic Era.

Material: Most of skull, left dentary, left splenial, left coronoid, right angular, right surangular, right articular, right ulna, a caudal vertebra, some dorsal osteoderms, and other postcranial fragments.

_____________________________________________________________________________________

Species: threensis BROCHU, PARRIS, GRANDSTAFF, DENTON & GALLAGHER, 2012
Etymology: Threensis, in reference to the question every New Jersey resident encounters when traveling: "Oh, you're from New Jersey? Which exit?" The type localitiy is most easily reached from the New Jersey Turnipke by taking Exit 3 and heading east on New Jersey Highway 168.

Holotype; NJSM 11902

Locality: Inversand marl pit in Sewell, Mantua Township, Gloucester County, New Jersey.

Horizon: Hornerstown Formation, Rancocas Group.

Biostratigraphy:

Age: Latest Maastrichtian Stage, uppermost Senonian subepoch, Gulf Epoch, Late Cretaceous.

Material: Isolated left ectoptrygoid and lower jaws with associated postcranial remains.

Referred material:

NJSM 11903: Vertebrae adn osteoderms.