Genus: Trierarchuncus FOWLER, WILSON, FREEDMAN FOWLER, NOTO, ANDUZA & HORNER, 2020
Etymology: In ancient Greek, the name of a seafaring ship's captian (trireme ships), and Latin, uncus, "hook."

Species: prairiensis FOWLER, WILSON, FREEDMAN FOWLER, NOTO, ANDUZA & HORNER, 2020
Etymology: 'of the prairie,' referring to the gentle plains of eastern Montana (in particular the American Prairie Reserve) where teh new material was discovered.

Holotype: MOR 6622

Locality: UCMP V80092, Sandstone Basin, South of Fort Peck Reservoir, near Jordan, Garfield County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian Age, Uppermost Maastrichtian Stage, Uppermost Senonian Subepoch, Uppermost Gulf Epoch, Uppermost Late Cretaceous.

Material: A manual MD-1-2, ungual.

Referred material:

HUTCHINSON & CHIPPE, 1998

UCMP 154584: Right pubis and partial ischium.

UCMP 154584: A) lateral view, B) medial view (after hutchinson & Chiappe, 1998), and C) reconstruction of the pelvis.

 

Locality: South of Fort Peck Reservoir, near Jordan, Garfield County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian Age, Uppermost Maastrichtian Stage, Uppermost Senonian Subepoch, Uppermost Gulf Epoch, Uppermost Late Cretaceous.

Material:

MOR 3098: MD -1 ungual.

MOR 2920: A 3rd metatarsal (MT-III).

 

Locality: North of Fort Peck Reservoir, near Jordan, Valley County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material:

BDM 001: Manual ungual MD-1.

BDM 002: A distal end of a left radius.

 

FRIEMUTH & WILSON, 2021

Locality: MOR locality HC-064, Makoshika State Park, near Glendive, quadrant Township 15N and Range 56E, Dawson County, Eastern Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material:

MOR 10889: A partial D-1 manual ungual.

 

Locality: DDM locality DDM-18-339, Carter County, southeast Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material:

DDM 1682.32: A near-complte D-1 manual ungual.