Ancon Point fauna (Basal Breccia) (Oligocene of Ecuador)

Where: Guayas, Ecuador (2.3° S, 80.9° W: paleocoordinates 4.2° S, 75.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Late/Upper Oligocene (28.4 - 23.0 Ma)

• SOURCE: assemblage collected from a single member (basal breccia). AGE: Upper Oligocene. STRAIGRAPHIC RELATIONS: the lower Oligocene at Ancon Point has been divided in six lithological units. The total thickness of the succession does not exceed 500 ft. The collection is from the "basal breccia", a sandstone averaging 35 ft thick. The breccia rests unconformably on the Eocene Seca Shale.

• member-level stratigraphic resolution

Environment/lithology: marine; lithified, conglomeratic sandstone

• ENVIRONMENT: no environmental data reported.
• SPECIFIC LITHOLOGY: a heterogeneous sandstone; contains casts and molds, hence must be lithified.

Size class: macrofossils

Preservation: cast, mold/impression

Reposited in the BMNH

Collection methods: quarrying, ,

• COLLECTOR: unknown collectors. REPOSITORIES: unknown repsotories

Primary reference: G. Shepard. 1937. The geology of south-western Ecuador. Published by AAPG; lists some otherwise unpublished faunal lists, identified by Woodring and Vaughan; nomenclature is antiquated. [A. Miller/A. Hendy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 61203: authorized by Austin Hendy, entered by Austin Hendy on 30.05.2006

Creative Commons license: CC BY (attribution)

Taxonomic list

• IDENTIFIER: BMNH staff. COVERAGE: probably not exhaustive, but nevertheless lengthy for gastropoda and bivalvia. No other groups mentioned. NOMENCLATURE: antiquated, but largely identified to species resolution.
Bivalvia
 Cardiida - Veneridae
Paphia sp. Röding 1798 venus clam
Pitar (Agriopoma) mancorensis Olsson 1931 venus clam
 Cardiida - Vesicomyidae
Pleurophopsis peruviana Olsson 1931 clam
Gastropoda
  -
Gastropoda indet. Cuvier 1795 snail
indet. casts
 Cerithiacea - Melaniidae
Anconia elenensis Olsson 1931 snail
 Neritoidea - Neritidae
Nerita sp. Linnaeus 1758 snail