Trigonias Quarry (Eocene of the United States)

Also known as Lower Quarry; Trigonias Quarries; Upper Quarry; Weld County Quarry

Where: Weld County, Colorado (40.8° N, 103.7° W: paleocoordinates 42.2° N, 95.2° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Chadron Formation, Chadronian (37.2 - 33.9 Ma)

• "probably equivalent to an early phase of the typical Titanotherium beds of the South Dakota Oligocene" (Wood 1931)

• member-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; volcaniclastic sediments

• the "Lower Quarry sediment" probably "represents an altered tuff" (Wood 1931)

Size class: macrofossils

Collection methods: Denver Museum of Natural History collection

Primary reference: W. K. Gregory and H. J. Cook. 1928. New material for the study of evolution: a series of primitive rhinoceros skulls (Trigonias) from the Lower Oligocene of Colorado. Proceedings of the Colorado Museum of Natural History 8(1):1-32 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 99642: authorized by John Alroy, entered by John Alroy on 17.11.2010

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Perissodactyla - Rhinocerotidae
"Trigonias osborni" = Trigonias osborni, "Trigonias preoccidentalis n. sp." = Trigonias osborni, "Caenopus premitis n. sp." = Trigonias osborni, "Trigonias precopei n. sp." = Trigonias osborni, "Trigonias hypostylus n. sp." = Trigonias osborni, "Trigonias taylori n. sp." = Trigonias osborni
"Trigonias osborni" = Trigonias osborni Lucas 1900 rhinoceros
types of "T. osborni secundus" and "T. osborni figginsi"
"Trigonias preoccidentalis n. sp." = Trigonias osborni Lucas 1900 rhinoceros
"Caenopus premitis n. sp." = Trigonias osborni Lucas 1900 rhinoceros
"Trigonias precopei n. sp." = Trigonias osborni Lucas 1900 rhinoceros
"Trigonias hypostylus n. sp." = Trigonias osborni Lucas 1900 rhinoceros
"Trigonias taylori n. sp." = Trigonias osborni Lucas 1900 rhinoceros
Aves
 Gruiformes - Rallidae
Palaeocrex fax n. gen. n. sp.
Palaeocrex fax n. gen. n. sp. Wetmore 1927 rail
 Gruiformes - Bathornithidae
Bathornis veredus n. gen. n. sp.
Bathornis veredus n. gen. n. sp. Wetmore 1927 bird
 Cathartiformes - Cathartidae
Phasmagyps patritus n. gen. n. sp., Palaeogyps prodromus n. gen. n. sp.
Phasmagyps patritus n. gen. n. sp. Wetmore 1927 vulture
Palaeogyps prodromus n. gen. n. sp. Wetmore 1927 vulture