Bed 20, Crisnejas section (Cretaceous of Peru)

Where: Peru (6.9° S, 78.0° W: paleocoordinates 12.4° S, 50.0° W)

• coordinate based on nearby landmark

• basin-level geographic resolution

When: Crisnejas Formation, Middle Albian (109.0 - 105.3 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: lithified, nodular, shelly/skeletal, gray, argillaceous limestone

• LITHOLOGY: Shale, bluish and purple, laminated, splintery, soft, with interbeds of light gray, nodular, fossiliferous, argillaceous limestone. LITHIFICATION: Lithified, on the basis of facies description.

Size class: macrofossils

Reposited in the AMNH

Collection methods: surface (in situ),

• COLLECTOR: V. E. Benavides. REPOSITORY: AMNH.

Primary reference: V.E. Benavides-Caceres. 1956. Cretaceous system in northern Peru. Bulletin of the American Museum of Natural History 108(4):1-493 [A. Miller/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 88175: authorized by Austin Hendy, entered by Austin Hendy on 02.04.2009, edited by Matthew Clapham

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for ammonoids, bivalves, and other invertebrates groups. NOMENCLATURE: Authoritative publication, but with somewhat antiquated nomenclature, and species-resolution identifications.
Show authors, comments, and common names
Echinoidea
 Irregularia - Nucleolitidae
"Botriopygus sp." = Pygorhynchus, "Echinobrissus sp." = Nucleolites
"Botriopygus sp." = Pygorhynchus sea urchin
"Echinobrissus sp." = Nucleolites Lamarck 1801 sea urchin
 Holectypoida - Holectypidae
"Holectypus planatus" = Coenholectypus neocomiensis
"Holectypus planatus" = Coenholectypus neocomiensis Gras 1848 sea urchin
 Spatangoida - Toxasteridae
Enallaster peruanus
Enallaster peruanus heart urchin
Bivalvia
 Ostreida - Ostreidae
"Ostrea cf. dieneri" = Lopha dieneri
"Ostrea cf. dieneri" = Lopha dieneri Blanckenhorn 1890 oyster
 Pholadomyida - Pholadomyidae
Pholadomya sp.
Pholadomya sp. Sowerby 1823 clam
 Trigoniida - Steinmanellidae
Yaadia hondoana
Cephalopoda
 Ammonitida - Knemiceratidae
Parengonoceras pernodosum
Parengonoceras pernodosum Sommermeier 1910 ammonite