USGS M8693 (Cretaceous of the United States)

Where: Medina County, Texas (29.3° N, 99.1° W: paleocoordinates 34.9° N, 72.5° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Baculites maclearni ammonoid zone, Anacacho Limestone Formation, Middle Campanian (83.5 - 70.6 Ma)

• Swezey and Sullivan (2004) correlate this bed to the Baculites maclearni zone., which is middle Campanian in Gradstein et al., 2004.

• bed-level stratigraphic resolution

Environment/lithology: marine; limestone

• lithology described as chalky limestone

Size class: mesofossils

Reposited in the USGS

Primary reference: W. P. Elder. 1996. Bivalves and Gastropods from the Middle Campanian Anacacho Limestone, south central Texas. Journal of Paleontology 70(2):247-271 [M. Patzkowsky/K. Layou/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 3604: authorized by Mark Patzkowsky, entered by Karen Layou on 05.08.1999

Creative Commons license: CC BY (attribution)

Taxonomic list

 Arcida - Arcidae
"cf. Arca carolinensis" = Barbatia carolinensis
"cf. Arca carolinensis" = Barbatia carolinensis Conrad 1849 clam
originally entered as "Arca cf. carolinensis"
 Arcida - Cucullaeidae
Cucullaea sp. Lamarck 1801 clam
 Myalinida - Inoceramidae
cf. Inoceramus balticus Bohm 1907 clam
originally entered as "Inoceramus cf. balticus"
 Pectinida - Pectinoidae
Neithea quinquecostata Sowerby 1814 scallop
 Pectinida - Limidae
 Ostreida - Gryphaeidae
 Cardiida - Cardiidae
Granocardium sp. Gabb 1868 cockle
 Hiatellida - Hiatellidae
Panopea anacachoensis n. sp. clam
originally entered as "Panopea anacachoensis n. sp."
 Solenida - Pharidae
aff. Leptosolen biplicata Conrad 1858 clam
originally entered as "Leptosolen aff. biplicatus"
 Poromyida - Poromyidae
cf. Cymella ironensis clam
originally entered as "Cymella cf. ironensis"
 Lucinida - Lucinidae
? Lucinidae indet. Fleming 1828 clam
originally entered as "?Lucinid indet."
 Trigoniida - Megatrigonioidae
Pterotrigonia sp. van Hoepen 1929 clam
 Nuculida - Nuculidae
cf. Nucula stantoni Stephenson 1923 nut clam
originally entered as "Nucula cf. stantoni"
 Stromboidea - Aporrhaidae
aff. Drepanocheilus cuthandensis snail
originally entered as "Drepanochilus? aff. cuthandensis"
 Ammonitida - Baculitidae
Baculites taylorensis Adkins 1929 ammonite
 Nautiloidea -
? Nautiloidea indet. Agassiz 1847 nautiloid
originally entered as "?Nautiloid indet."