LACM 7170, El Rosario (Cretaceous of Mexico)

Where: Baja California, Mexico (30.2° N, 115.8° W: paleocoordinates 35.7° N, 86.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: El Gallo Formation, Late/Upper Campanian (83.5 - 70.6 Ma)

• said to be Campanian

• formation-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size classes: macrofossils, mesofossils

Collected by H. Garbani, M. Greenwald in 1970, 1973; reposited in the LACM

Collection methods: bulk, quarrying, surface (float), surface (in situ), sieve,

• collections were eventually moved from the LACM to the IGM (Nydam 1999)

Primary reference: R. L. Nydam. 1999. Polyglyphanodontinae (Squamata: Teiidae) from the medial and Late Cretaceous: new taxa from Utah, U.S.A. and Baja California del Norte, Mexico. Utah Geological Survey Miscellaneous Publication 99-1:303-317 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 231484: authorized by Matthew Carrano, entered by Matthew Carrano on 21.08.2023

Creative Commons license: CC BY (attribution)

Taxonomic list

• Ferrusquia 1978 claims there is a "radiometric" date of 73 Ma, which if true places close to the Campanian - Maastrichtian boundary. Said to be Campanian based on ammonites. Date is K-Ar reported in ref 30749 as 73 ± 2 Ma.
Show authors, comments, and common names
Reptilia
 Squamata - Polyglyphanodontidae
"Polyglyphanodon bajaensis" = Dicothodon bajaensis
"Polyglyphanodon bajaensis" = Dicothodon bajaensis Nydam 1999 squamates
IGM 6964 (= LACM 57877)