JR-248 (Cambrian of the United States)

Where: Mason County, Texas (30.6° N, 99.3° W: paleocoordinates 15.7° S, 98.5° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Aphelaspis trilobite zone, Lion Mountain Member (Riley Formation), Paibian (497.0 - 494.0 Ma)

• Aphelaspis zone is within North American Steptoean stage

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified limestone and lithified, glauconitic sandstone

• highly glauconitic sandstone containing in the lower part numerous tangential lenses of limestone composed essentially of trilobite remains

Size class: macrofossils

Collected by A. R. Palmer in the 1940s; reposited in the USNM

Collection methods: mechanical,

Primary reference: A. R. Palmer. 1954. The Faunas of the Riley Formation in Central Texas. Journal of Paleontology 28(6):709-786 [P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 208616: authorized by Melanie Hopkins, entered by Melanie Hopkins on 07.04.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Lingulata
 Acrotretida - Acrotretidae
Angulotreta triangularis digitalis
Trilobita
 Olenida - Aphelaspidae
Labiostria conveximarginata, Aphelaspis walcotti
Labiostria conveximarginata Palmer 1954 trilobite
Aphelaspis walcotti Resser 1938 trilobite