Species: gilberti LYSON, SAYER & JOYCE, 2019 (published 2020)
Etymology:
Holotype: DMNH EPV.96000
Locality: DMNH Loc. 6302 (Turtle Ridge Locality), northwest of Marmarth, Buckling Townshipe, Slope County, North Dakota.
Horizon: Hell Creek Formation.
Biostratigraphy:
Age: Lancian Age, upper Maastrichtian Stage, uppermost Senonian Subepoch, Upper Upper Gulf Epoch, Late Cretaceous.
Material: An articulated skull, mandible, and hyoid apparatus.
Referred material:
DMNH EPV.96903: Two-thirds of shell.
DMNH EPV.96905: Well-preserved carapace with medial sutures and sulci clearly visible and nearly complete plastron, altough sutures and sulci are obscured.
DMNH EPV.96907: Partially complete carapace and plastron.
DMNH EPV.96903: Two-thirds of a shell.
DMNH EPV.96908: Shell.
DMNH EPV.96909: Carapace.
DMNH EPV.96910: Shell.
DMNH EPV.97026: Carapace and plastron fragments.
DMNH EPV.97029: Skeleton with distorted skull and articulated lower jaw, isolated cervical vertebrae, complete shell, 13 articulated caudal vertebrae, both humeri, and both hind limbs and let pes.
DMNH EPV.97030: Nearly complete plastron.
DMNH EPV.97031: Carapace and plastron fragments.
DMNH EPV.97033: Skull roof, and mostly complete shell.
DMNH EPV.97034: Skull roof.
DMNH EPV.97035: Left plastron and hypoplastron.
DMNH EPV.97041: A near complete skull, missing part of posterior ventral portion on the right side, with some crushing.
DMNH EPV.97042: A mostly complete shell.
DMNH EPV.97043: Shell.
DMNH EPV.97044: Shell.
DMNH EPV.97046: Shell.
DMNH EPV.97047: Shell.
DMNH EPV.97049: Posterior half of carapace with well-preserved in situ left hind limb and tail.
DMNH EPV.97066: Partial in situ shell.
DMNH EPV.97067: Complete in situ shell.
DMNH EPV.97068: Complete in situ shell.
DMNH EPV.97069: Complete in situ shell.
DMNH EPV.97070: In situe shell and associate manus.
DMNH EPV.97071: Complete shell in situ.
DMNH EPV.98789: Plastron.
DMNH EPV.98812: Complete carapce and plastron with sutures and sulci.
DMNH EPV.98816: Nearly complete mandible, missing part of the dorsal portion of the right side.
DMNH EPV.98820: Shell fragments.
DMNH EPV.98828: Partial shell.
DMNH EPV.98829: Anterior half of plastron.
DMNH EPV.98830: Shell fragments.
DMNH EPV.98849: Shell fragments.
DMNH EPV.98850: Skull roof.
DMNH EPV.98851: Plastron fragment.
DMNH EPV.98857: Plastron with carapace fragments.
DMNH EPV.98861: A complete mandible.
DMNH EPV.130939: An almost complete skull.
DMNH EPV.130969: Plastron elements.
DMNH EPV.14014.02: Skeleton with complete shell and skull, as well as a partial caudal series, forelimb, and hindlimb.