Where: New Castle County, Delaware (39.8° N, 75.6° W: paleocoordinates 39.2° N, 45.5° W)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: Didymoceras cheyennense ammonoid zone, Mount Laurel Sand Formation, Late/Upper Campanian (83.5 - 70.6 Ma)
• STRATIGRAPHIC RELATIONS: From the Mount Laurel Sand, which regionally overlies the Marshalltown Fm (Campanian), and is unconformably overlain by the Columbia Fm (Quaternary). AGE: Late Campanian, on the basis of ammonite biostratigraphy; Didymoceras cheyennense zone and part of the Baculites compressus zone. STRATIGRAPHIC POSITION: From beds within section of 8 ft in thickness.
• group of beds-level stratigraphic resolution
Environment/lithology: coastal; lithified, burrowed, phosphatic, silty sandstone
Size class: macrofossils
Preservation: cast, mold/impression, replaced with phosphate
Reposited in the USNM
Collection methods: surface (in situ),
• COLLECTORS: Multiple collectors, including members of the Monmouth Amateur Paleontologists Society (MAPS). REPOSITORY: USNM and Monmouth Amateur Paleontologists Society (MAPS).
Primary reference: W. J. Kennedy and W. A. Cobban. 1994. Upper Campanian ammonites from the Mount Laurel Sand at Biggs Farm, Delaware. Journal of Paleontology 68(6):1285-1305 [A. Hendy/A. Hendy]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 83133: authorized by Austin Hendy, entered by Austin Hendy on 07.08.2008, edited by Matthew Clapham
Creative Commons license: CC BY (attribution)
Taxonomic list
Thecostraca | |
Cretiscalpellum homseyi n. sp.
Cretiscalpellum homseyi n. sp. Zullo 1987 barnacle | |
"Brachylepas solida n. sp." = Myolepas solida
"Brachylepas solida n. sp." = Myolepas solida Zullo 1987 barnacle | |
Arcoscalpellum bakeri Collins 1973 barnacle
Arcoscalpellum withersi Collins 1973 barnacle | |
Cephalopoda | |
Placenticeras sp. Meek 1876 ammonite
Placenticeras cf. placenta DeKay 1828 ammonite | |
Pachydiscus (Pachydiscus) sp. Zittel 1884 ammonite | |
? Eulophoceras sp. Hyatt 1903 ammonite | |
Hoploscaphites vistulensis Blaszkiewicz 1980 ammonite
Jeletzkytes compressus Roemer 1841 ammonite | |
Baculites undatus Stephenson 1941 ammonite
Baculites ovatus Say 1820 ammonite | |
Solenoceras annulifer, "Oxybeloceras meekanum" = Spiroxybeloceras meekanum
Solenoceras annulifer Morton 1824 ammonite
"Oxybeloceras meekanum" = Spiroxybeloceras meekanum Whitfield 1877 ammonite | |
Didymoceras cheyennense, "Nostoceras (Nostoceras) draconis" = Didymoceras draconis, Anaklinoceras reflexum, Anaklinoceras tenuicostatum
Didymoceras cheyennense Meek and Hayden 1856 ammonite
"Nostoceras (Nostoceras) draconis" = Didymoceras draconis Stephenson 1941 ammonite
Anaklinoceras reflexum Stephenson 1941 ammonite
Anaklinoceras tenuicostatum Kennedy and Cobban 1994 ammonite |