CSUN Loc. 471b, Chivo Canyon, Santa Susana Mountains (Eocene of the United States)

Where: Ventura County, California (34.3° N, 118.7° W: paleocoordinates 36.8° N, 101.7° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Llajas Formation, Ypresian (56.0 - 47.8 Ma)

• From lower Llajas Formation, lower "Domengine" stage, base of CP12a calcareous nannoplankton zone, upper Ypresian stage, Lower Eocene, C22n chron.

• bed-level stratigraphic resolution

Environment/lithology: offshore; sandstone and argillaceous siltstone

• Alternating laminated and bioturbated sandstones grading into muddy siltstone.

Size class: macrofossils

Preservation: mold/impression

Reposited in the LACM

• Collected by R.L. Squires (1978)

Primary reference: R. L. Squires. 1984. Megapaleontology of the Eocene Llajas Formation, Simi Valley, California. Contributions in Science, Natural History Museum of Los Angeles County 350:1-76 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 201247: authorized by Jonathan Marcot, entered by Jonathan Marcot on 02.05.2019

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for mollusca, corals, arthropoda, and includes other groups where obvserved; list compiled from meticulous search of the invert collections at the LACM, private collections and fieldwork.
Show authors, comments, and common names
Bivalvia
 Ostreida - Malleidae
Nayadina (Exputens) llajasensis
Gastropoda
 Architaenioglossa - Ampullinidae
Eocernina hannibali
Eocernina hannibali Dickerson 1914 snail
 Sorbeoconcha - Cassidae
Phalium (Semicassis) tuberculiformis
Malacostraca
 Decapoda - Euryplacidae
"Glyphithyreus weaveri" = Orbitoplax weaveri
"Glyphithyreus weaveri" = Orbitoplax weaveri Rathbun 1926 crab