UCMP 3579, east of Mount Diablo (Eocene of the United States)

Where: Contra Costa County, California (37.9° N, 121.7° W: paleocoordinates 40.5° N, 104.5° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Meganos Formation, Ypresian (56.0 - 47.8 Ma)

• "Meganos" faunas represent upper Bulitian and lower Penutian local ages=Ypresian

• bed-level stratigraphic resolution

Environment/lithology: coastal; lithified, fine-grained, pebbly, calcareous sandstone

• Shallow marine coastal siliciclastic environment
• Fine, micaceous sandstone, commonly with small pebbles, thinly beeded near bottom, more massive at top, yellow-brown to gray in color. The massive sandstones near top contain lenses of harded calcareous and fossiliferous sandstones.

Size class: macrofossils

Reposited in the UCMP

Collection methods: quarrying,

• Collected by Clark and Woodford. Collections reposited at UCMP.

Primary reference: B. L. Clark and A. O. Woodford. 1927. The geology and paleontology of the type section of the Meganos Formation (lower Middle Eocene) of California. University of California Publications in Geological Sciences 17(2):63-142 [A. Miller/A. Hendy/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 52430: authorized by Austin Hendy, entered by Austin Hendy on 05.08.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

• Identified by Clark and Stewart.
Show authors, comments, and common names
Gastropoda
 Heterostropha - Pyramidellidae
Odostomia diaboli, Turbonilla marshensis n. sp.
Odostomia diaboli Clark and Woodford 1927 snail
Turbonilla marshensis n. sp. Clark and Woodford 1927 snail
 Sorbeoconcha - Naticidae
Polinices (Euspira) nuciformis
Polinices (Euspira) nuciformis Gabb 1864 moon snail
 Neogastropoda - Nassariidae
Molopophorus californicus n. sp.
Molopophorus californicus n. sp. Clark and Woodford 1927 snail
 Neogastropoda - Buccinidae
"Chrysodomus" martini
"Chrysodomus" martini Dickerson 1913 true whelk
 Neogastropoda - Clavatulidae
? Turricula cooperi
? Turricula cooperi Dickerson 1916 snail
 Neogastropoda - Turridae
Gemmula diabloensis n. sp.
Gemmula diabloensis n. sp. Clark and Woodford 1927 turrid
Bivalvia
 Nuculanida - Nuculanidae
"Leda gabbi" = Nuculana (Saccella) gabbii
"Leda gabbi" = Nuculana (Saccella) gabbii Conrad 1866 pointed nut clam
 Mytilida - Mytilidae
"Modiolus (Brachydontes) ornatus" = Brachidontes (Brachidontes) cowlitzensis
"Modiolus (Brachydontes) ornatus" = Brachidontes (Brachidontes) cowlitzensis Weaver and Palmer 1922 mussel
 Ostreida - Ostreidae
Ostrea sp.
Ostrea sp. Linnaeus 1758 oyster
 Arcida - Arcidae
"Arca hornii" = Pachecoa hornii
"Arca hornii" = Pachecoa hornii Gabb 1864 clam
Subspecies: Arca hornii elusa
 Cardiida - Tellinidae
"Tellina longa" = Tellina (Angulus) longa
"Tellina longa" = Tellina (Angulus) longa Gabb 1864 tellin clam
 Cardiida - Ungulinidae
"Diplodonta cretacea" = Diplodonta (Diplodonta) cretacea
"Diplodonta cretacea" = Diplodonta (Diplodonta) cretacea Gabb 1864 clam
 Cardiida - Veneridae
Tivela kelloggensis
Tivela kelloggensis Clark and Woodford 1927 venus clam
 Cardiida - Mactridae
"Spisula meganosensis n. sp." = Pseudocardium meganosensis
"Spisula meganosensis n. sp." = Pseudocardium meganosensis Clark and Woodford 1927 clam
 Pholadida - Myidae
? Sphenia meganosensis n. sp.
? Sphenia meganosensis n. sp. Clark and Woodford 1927 softshell clam
 Pholadida - Corbulidae
"Corbula dilatata" = Caryocorbula complicata
"Corbula dilatata" = Caryocorbula complicata Hanna 1924 clam