SS-30, Simpson Springs Mountains (Ordovician of the United States)

Also known as Marathon Uplift, Woods Hollow Fm., Tremadoc?, Texas

Where: Texas (30.0° N, 103.3° W: paleocoordinates 16.5° S, 92.4° W)

• coordinate based on political unit

When: Upper Member (Woods Hollow Boulders Formation), Gasconadian (485.4 - 477.7 Ma)

• possibly not Tremadoc.

Environment/lithology: glauconitic, green limestone

• "ls boulders in dark green sh. outer shelf. BA5"
• Brownish gray mottled with purplish tinge, fine-grained, slightly sandy limestone of fragmental texture, with glauconitic matrix and phenoclasts of pink fine-grained limestone; some calcirudite mixed with fine-grained limestone; weathers purplish and is highly jointed.

Size class: macrofossils

Primary reference: J.L. Wilson. 1954. Late Cambrian and Early Ordovician Trilobites from the Marathon Uplift, Texas. Journal of Paleontology 28(3):249-285 [P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 282: authorized by Jack Sepkoski, entered by Mike Sommers on 20.11.1998, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

• "Wilson 1954"
Conodonta
 Prioniodontida - Oistodontidae
Oistodus sp. Pander 1856 conodont
Gastropoda
 Eogastropoda - Sinuopeidae
"Rhombella ? umbilicata" = Euconia umbilicata
"Rhombella ? umbilicata" = Euconia umbilicata Dake and Bridge 1932 snail
Cephalopoda
 Orthocerida - Baltoceratidae
Baltoceratidae indet. Kobayashi 1935
Artiopoda
 Agnostida - Metagnostidae
Geragnostus sp. Howell 1935
 Agnostida - Diplagnostidae
Pseudagnostus sp. Jaekel 1909
 Agnostida - Agnostidae
Homagnostus sp. Howell 1935
Trilobita
 Proetida - Dimeropygidae
Pseudohystricurus sp. Ross 1951 trilobite
 Proetida - Hystricuridae
Parahystricurus sp. Ross 1951 trilobite
 Corynexochida - Illaenuridae
"Platycolpus sp." = Rasettia
"Platycolpus sp." = Rasettia Lochman 1953 trilobite
 Olenida - Olenidae
Parabolinella sp. Brögger 1882 trilobite