Where: Jalisco, Mexico (20.1° N, 104.1° W)

• Paleocoordinates: 22.1° N, 101.7° W (Wright 2013)

• coordinate stated in text

When: Hh3 mammal zone, San Jose Formation, Hemphillian (10.3 - 4.9 Ma)

• Age control in the localities comes from volcanic ash at the top of the sequence and late Hemphillian

•faunas (Hh3). The volcanic ash was dated at 4.89 ± 0.16 Ma by 40Ar/39Ar

•(Kowallis et al., 1998). Just above this volcanic ash, lenses of sandstone rich in small vertebrates crops out, mainly yielding cricetid rodents, lagomorphs, fishes, amphibians, reptiles and birds

Environment/lithology: fluvial; sandstone

Size classes: macrofossils, mesofossils

Collection methods: surface (float), sieve,

Primary reference: A. Pacheco Castro, O. Carranza Castañeda, and E. Jiménez Hidalgo. 2019. A new species of Sigmodontinae (Rodentia) from the late Hemphillian of central Mexico, and comments on the possible radiation of this group. Revista Mexicana de Ciencias Geológicas 36(3):321-342 [P. Holroyd/P. Holroyd]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 232513: authorized by Patricia Holroyd, entered by Patricia Holroyd on 01.12.2023

Creative Commons license: CC0 (CC0)