USGS Cenozoic M1935 Walker Canyon (Miocene of the United States)

Also known as UCMP IP6939

Where: Monterey County, California (36.0° N, 120.8° W: paleocoordinates 35.2° N, 116.4° W)

• coordinate stated in text

When: Pancho Rico Formation, Miocene (23.0 - 5.3 Ma)

• Described in reference as Pliocene. Pancho Rico Formation is Miocene per Addicott 1978 (Geological Survey Bulletin, Issue 1457).

Environment/lithology: marine; lithology not reported

• Medium- and coarse-grained sandstone, locally pebbly, and interbedded mudstone. The ledgeforming bed at the top of the outcrop contains abundant fossil echinoids.

Size class: macrofossils

Collected by D. L Durham, W. O. Addicott in 1963

Primary reference: D. L. Durham and W. O. Addicott. 1965. Pancho Rico Formation, Salinas Valley. United States Geological Survey Professional Paper 524(A):A1-A22 [P. Holroyd/S. Tremblay]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 194895: authorized by Patricia Holroyd, entered by Susan Tremblay on 06.07.2018

Creative Commons license: CC BY (attribution)

Taxonomic list

Maxillopoda
 Sessilia - Balanidae
Balanus sp. Da Costa 1778 barnacle
Bivalvia
 Arcida - Glycymerididae
 Pectinida - Pectinoidae
 Ostreida - Ostreidae
"Ostrea atwoodi" = Ostrea (Ostrea) atwoodii
"Ostrea atwoodi" = Ostrea (Ostrea) atwoodii Gabb 1866 oyster
 Carditida - Carditidae
"Cyclocardia californica" = Coanicardita californica Dall 1903 clam
Glans "n. sp. aff radiata" Mühfeld 1811 clam
 Cardiida - Mactridae
"Spisula hemphilli" = Mactromeris hemphillii
"Spisula hemphilli" = Mactromeris hemphillii Dall 1894 clam
 Cardiida - Veneridae
"Protothaca cf. lacinata" = Leukoma, "? Protothaca tenerrima" = Callithaca tenerrima, "Transenella tantilla" = Nutricola tantilla
"Protothaca cf. lacinata" = Leukoma venus clam
subsp. hannibali
"? Protothaca tenerrima" = Callithaca tenerrima Carpenter 1857 venus clam
"Transenella tantilla" = Nutricola tantilla Gould 1853 venus clam
 Cardiida - Tellinidae
"Florimetis biangulata" = Psammotreta (Leporimetis) obesa Deshayes 1855 tellin clam
Tellina cf. aragonia Dall 1909 tellin clam
"Tellina cf. lutea" = Tellina (Megangulus) lutea Gray 1828 tellin clam
"Macoma secta" = Macoma (Rexithaerus) secta Conrad 1837 tellin clam
Macoma nasuta Conrad 1837 tellin clam
 Cardiida - Psammobiidae
"Sanguinolaria cf. nuttalli" = Nuttallia nuttallii
"Sanguinolaria cf. nuttalli" = Nuttallia nuttallii Conrad 1837 clam
 Cardiida - Cardiidae
"Trachycardium quadragenarium" = Dallocardia quadragenarium
"Trachycardium quadragenarium" = Dallocardia quadragenarium Conrad 1837 cockle
 Solenida - Solenidae
Solen sp. Linnaeus 1758 clam
 Protobranchia - Yoldiidae
Yoldia sp. Möller 1842 clam
Field identification.
Gastropoda
  - Siphonaliidae
 Neogastropoda - Columbellidae
Mitrella sp. Risso 1826 snail
 Neogastropoda - Nassariidae
"Nassarius cf. californianus" = Caesia californiana
"Nassarius cf. californianus" = Caesia californiana Conrad 1856 snail
 Neogastropoda - Cancellariidae
"Cancellaria cf. fernandoensis" = Euclia fernandoensis
"Cancellaria cf. fernandoensis" = Euclia fernandoensis Arnold 1907 snail
 Neogastropoda - Muricidae
Forreria belcheri murex snail
Ocenebra cf. tethys murex snail
 Neogastropoda - Turridae
 Naticoidea - Naticidae
Sinum cf. scopulosum, "Neverita cf. recluziana" = Glossaulax reclusiana
Sinum cf. scopulosum Conrad 1849 moon snail
"Neverita cf. recluziana" = Glossaulax reclusiana Deshayes 1841 moon snail
 Calyptraeoidea - Calyptraeidae
Crucibulum "n. sp. ?" Schumacher 1817 slipper shell
Crepidula cf. nummaria Gould 1846 slipper shell
Crepidula cf. onyx Sowerby 1824 slipper shell
 Sorbeoconcha - Turritellidae
 Sorbeoconcha - Procerithiidae
"Bittium casmaliense" = Lirobittium casmaliense
"Bittium casmaliense" = Lirobittium casmaliense Bartsch 1911 snail
 Trochoidea - Trochidae
"Margarites aff. pupillus" = Pupillaria pupilla
"Margarites aff. pupillus" = Pupillaria pupilla Gould 1849 top snail
Echinoidea
 Clypeasteroida - Echinarachniidae
Astrodapsis sp. sand dollar
"Astrodapsis spatiosus" = Astrodapsis arnoldi spatiosus Kew 1920 sand dollar
 Clypeasteroida - Dendrasteridae
Dendraster sp. Agassiz and Desor 1847 sand dollar