Abundance: 0.21 to 4.00% (median 1.49%)

Latitudinal range: 41.5° to 44.9°

Habitats: (8) only

Found in 8 samples

United States: Holly's Microsite (Late Palaeocene), UMMP SC-4 (Early Eocene), UMMP SC-54 (Early Eocene), UMMP SC-67 (Early Eocene), Fossil Butte (FB-16) (Early Eocene), UCMP locality V77064 (Early Eocene), Deadman Butte (Early Eocene), Cooper Creek (Early Eocene)

See also Esthonyx acutidens, Esthonyx ancylion, Esthonyx bisulcatus, Esthonyx grangeri, Esthonyx gunnelli, Esthonyx sp., Esthonyx spatularius