Nortwest slope of the Knob (Jurassic of the United States)

Where: California (40.1° N, 120.8° W: paleocoordinates 33.5° N, 60.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Labyrinthoceras ammonoid zone, Mormon Sandstone Member (Mormon Formation), Bajocian (170.3 - 168.3 Ma)

• Bajocian based on ammonites of faunas 4-5 of Crickmay's 1933 report on Mt. Jura. (Labyrinthoceras sp. and Sonninia mollis)

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, fine-grained, volcaniclastic, gray, green, red, muddy, conglomeratic sandstone

• Mainly fine gray arkose, with red and green conglomerate of volcanic debris at the base, and fine, dark gray paper shales at top

Size class: macrofossils

Reposited in the GSC

Primary reference: C. H. Crickmay. 1933. Attempt to Zone the North American Jurassic on the Basis of its Brachiopods. Geological Society America Bulletin 44:871-894 [M. Clapham/M. Manojlovic]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 164664: authorized by Matthew Clapham, entered by Marko Manojlovic on 09.12.2014

Creative Commons license: CC BY (attribution)

Taxonomic list

Rhynchonellata
 Terebratulida - Postepithyrididae
Euidothyris lucerna n. sp. Crickmay 1933
 Rhynchonellida - Cyclothyrididae
Flabellirhynchia falconis n. sp. Crickmay 1933
Flabellirhynchia concinna n. sp. Crickmay 1933