USGS Coll. 8-CO (Cambrian of the United States)

Where: Burnet County, Texas (30.8° N, 98.4° W: paleocoordinates 16.5° S, 98.3° W)

• coordinate estimated from map

• outcrop-level geographic resolution

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

• Member is either Lion Mountain or upper Cap Mountain

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified limestone

• either from upper limy portion of Cap Mountain limestone member or calcareous lenses in Lion Mountain sandstone member

Size class: macrofossils

Collected by Dake, Bridge, Ulrich in 1930-1934; reposited in the USGS

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 208982: authorized by Melanie Hopkins, entered by Melanie Hopkins on 20.04.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

 Billingsellida - Billingsellidae
Billingsella sp. Hall and Clarke 1892
 Acrotretida - Acrotretidae
 Agnostida - Diplagnostidae
Pseudagnostus communis Hall and Whitfield 1877
 Olenida - Aphelaspidae
Aphelaspis constricta n. sp. Palmer 1954 trilobite
Aphelaspis walcotti Resser 1938 trilobite
Aphelaspis longifrons Palmer 1954 trilobite
Labiostria conveximarginata Palmer 1954 trilobite
 Ptychopariida - Elviniidae
Dytremacephalus laevis Palmer 1954 trilobite
Dunderbergia variagranula Palmer 1954 trilobite
 Corynexochida - Cheilocephalidae
"Cheilocephalus breviloba" = Cheilocephalus brevilobus
"Cheilocephalus breviloba" = Cheilocephalus brevilobus Walcott 1916 trilobite