Where: Los Angeles County, California (36.9° N, 120.9° W: paleocoordinates 43.0° N, 96.3° W)

When: Moreno Formation (Great Valley Group), Maastrichtian (72.1 - 66.0 Ma)

• "The zone in which these examples were found is in the lower part of the Upper Asuncion group, mapped on the geologic sheet of Bull. 603 (U. S. Geol. Survey) as the Moreno for­ mation. The chronological position of the species, as determined from the stratigraphic se­quence underlying it, and as determined by the faunas of the underlying and overlying beds, is that of the middle or lower part of the Maestrichtian stage."

Environment/lithology: marine; conglomerate and pebbly, conglomeratic shale

Size class: macrofossils

Collected by J.M. Alderson in 1983; reposited in the LACM

Primary reference: F. M. Anderson. 1958. Upper Cretaceous of the Pacific Coast. Geological Society of America Memoir 71:1-378 [A. Miller/A. Hendy/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 215321: authorized by Jonathan Marcot, entered by Jonathan Marcot on 09.11.2020

Creative Commons license: CC BY (attribution)