Brick plant Quarry, southwest edge of the Ada. NE1/4 SE1/4 sec. 4 T3N, R6E (Carboniferous of the United States)

Also known as Helminthochiton from the Francis Formation of Oklahoma

Where: Oklahoma (34.8° N, 96.7° W: paleocoordinates 6.0° S, 31.4° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Francis Formation, Missourian (305.9 - 303.4 Ma)

• formation-level stratigraphic resolution

Environment/lithology: offshore; lithified shale

• The Francis Formation as exposed in the quarry is a dark-gray to black shale and mudstone which weathers in a blocky fashion. An abundant assortment of fossils is present which represents a diverse assemblage of shallow-water forms. Crinoid fragments are especially abundant, including numberous dorsal cups and a few complete crowns.

Primary reference: G. D. Morgan. 1924. Geology of the Stonewall quadrangle, Oklahoma. Oklahoma Bureau of Geology Bulletin 2:1-149 [P. Wagner/P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 39813: authorized by Pete Wagner, entered by Kimberly Koverman on 07.06.2004, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

• Lophophyllidium profundum, Echinocrinus sp., Crurithyris planoconvexa, Chonetes granulifer, Kozlowskia splendens, Linoproductus prattenianus, Neospirifer dunbari, Astartella vera, Ameura major are reported from the Francis Formation by Morgan (1924, p. 116-118). These were added as the primary reference, although it is only implied that Frederickson found these himself at this particular locality.
 Proetida - Phillipsiidae
Ameura major trilobite
 Carditida - Astartidae
Astartella vera Hall 1858 clam
 Neoloricata - Lepidopleuridae
Helminthochiton riddlei Frederickson 1962 chiton
Echinocrinus sp. Agassiz 1841 sea urchin
 Productida - Productidae
 Productida - Linoproductidae
Linoproductus prattenianus Norwood and Pratten 1855
 Productida - Rugosochonetidae
"Chonetes granulifer" = Neochonetes granulifer
"Chonetes granulifer" = Neochonetes granulifer Owen 1852
 Spiriferida - Trigonotretidae
 Spiriferida - Ambocoeliidae
 Stauriida - Lophophyllidiidae
Lophophyllidium profundum Milne-Edward and Haime 1851 horn coral