Species: natatrix ZANGERL, 1953
Etymology:

Holotype: FMNH PR220

Locality: 1 mile north of the Pyramids, Logan County, Kansas.

Horizon: Niobrara Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material: Partial carapace and plastron, scapulae, coracoid, limb-bones, and vertebrae of a juvenile.

Referred material:

Locality: Unknown, Kansas.

Horizon: Niobrara Formation?

Biostratigraphy:

Age: Late Cretaceous.

Material:

YPM 3606: Peripherals, and neurals.

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Species: niobrarae ZANGERL, 1953
Etymology:

Holotype: FMNH UR1

Locality: Kansas.

Horizon: Niobrara Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material: Partial carapace of a juvenile.

Referred material:

FMNH UR2: Plastron of an individual the size of UR1.

FMNH UR7: Partial plastron, pygal plate, ilium.

 

BRINKMAN, 2001

Locality: Chin Coulee, District of Taber, Alberta Province, Canada.

Horizon: Foremost Formation, Lower Judith River Group.

Biostratigraphy:

Age: Judithian Middle Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material:

RTMP 97.99.1: Skull and lower jaw.

 

Locality: South of Lethbridge, Lethbridge County, Alberta Province, Canada.

Horizon: Bearpaw Formation.

Biostratigraphy:

Age: Upper Campanian-Maastrichtian Stage, Upper Senonian Subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

RTMP 2000.55.1: Slightly crushed skull.

 

NICHOLLS, TOKARYK, & HILLS, 1990

Locality: East bank of the St. Mary River, NE ¼, sec.2, tp. 6, rge 22, WM4, Alberta Province, Canada.

Horizon: Bearpaw Formation.

Biostratigraphy:

Age: Upper Campanian-Maastrichtian Stage, Upper Senonian Subepoch, Upper Gulf Epoch, Late Cretaceous.

Maaterial:

RTMP 89.47.1: Articulated carapace and plastron.

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Species: venatrix ZANGERL, 1953
Etymology:

Holotype: FMNH P27355

Locality: Moore Brothers Farm, Harrel Station Area, Dallas County, Alabama.

Horizon: Mooreville Chalk, Selma Formation.

Biostratigraphy: Middle Tylosaurus Acme-zone – Clidastes Acme zone.

Age: Niobraran age, Upper Santonian-Lower Campanian Stage, Senoniain Subepoch, Gulf Epoch, Late Cretaceous.

Material: Fragmentary specimen.

Referred material:

Locality: Harrell Station area, Dallas County, Alabama.

Horizon: Mooreville Chalk, Selma Formation.

Biostratigraphy: Middle Tylosaurus Acme-zone – Clidastes Acme zone.

Age: Niobraran age, Upper Santonian-Lower Campanian Stage, Senoniain Subepoch, Gulf Epoch, Late Cretaceous.

Material:

FMNH P27426: Peripherals and costal plates.

FMNH P27350: Nuchal and peripherals.

 

Locality: Mt. Hebron area, Green County, Alabama.

Horizon: Mooreville Chalk, Selma Formation.

Biostratigraphy: Middle Tylosaurus Acme-zone – Clidastes Acme zone.

Age: Niobraran age, Upper Santonian-Lower Campanian Stage, Senoniain Subepoch, Gulf Epoch, Late Cretaceous.

Material:

FMNH PR22: 3 perpherals.