78SK57 - Unit 3 (top) (Miocene of the United States)

Also known as B-545

Where: Calvert County, Maryland (38.4° N, 76.5° W: paleocoordinates 38.6° N, 73.6° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Drumcliff Member (Choptank Formation), Serravallian (13.8 - 11.6 Ma)

• STRATIGRAPHIC RELATIONS: From Drumcliff Mbr of the Choptank Fm, Chesapeake Grp. AGE: Middle Miocene. STRATIGRAPHIC POSITION: From top of unit 3.

• bed-level stratigraphic resolution

Environment/lithology: coastal; unlithified, fine-grained, shelly/skeletal sandstone

• ENVIRONMENT: Shallow marine siliciclastic.
• SPECIFIC LITHOLOGY: Hashy, shell-supported fine sand. LITHIFICATION: Unlithified, based on visual inspection of collection by enterer.

Size class: macrofossils

Collected by Kidwell in 1978; reposited in the YPM

Collection methods: bulk, sieve,

• COLLECTOR: S.K. Kidwell, 1978. REPOSITORY: Peabody Museum of Natural History, Yale University.

Primary reference: S. M. Kidwell. 1982. Stratigraphy, invertebrate taphonomy and depositional history of the Miocene Calvert and Choptank Formations, Atlantic Coastal Plain. Unpublished PhD thesis, Yale University 1-511 [A. Hendy/A. Hendy/A. Hendy]more details

Purpose of describing collection: taphonomic analysis

PaleoDB collection 79108: authorized by Austin Hendy, entered by Austin Hendy on 25.02.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for gastropoda, bivalvia, and scaphopoda. NOMENCLATURE: Somewhat modern. Identifications are based on Martin (1904) for gastropods and bivalves, with revisions following subsequent publications.
Gastropoda
 Trochoidea - Trochidae
Calliostoma aphelium Dall 1892 top snail
 Neotaenioglossa - Calyptraeidae
Crepidula plana Say 1822 slipper shell
Crucibulum sp. Schumacher 1817 slipper shell
"Crucibulum ? constrictum" = Crucibulum (Dispotaea) constrictum Conrad 1842 slipper shell
 Cerithioidea - Turritellidae
"Turritella plebeia" = Mariacolpus plebeia, "Turritella variabilis" = Turritella (Torcula) variabilis
"Turritella plebeia" = Mariacolpus plebeia Say 1824 turret shell
"Turritella variabilis" = Turritella (Torcula) variabilis Conrad 1830 turret shell
 Neogastropoda - Muricidae
Ecphora sp. Conrad 1843 murex snail
 Sorbeoconcha - Naticidae
"Lunatia heros" = Euspira heros, "Polinices duplicatus" = Neverita duplicatus
"Lunatia heros" = Euspira heros Say 1822 moon snail
"Polinices duplicatus" = Neverita duplicatus Say 1822 moon snail
Bivalvia
 Arcida - Arcidae
"Anadara staminea" = Dallarca staminea
"Anadara staminea" = Dallarca staminea Say 1832 clam
 Pectinida - Pectinoidae
"Chesapecten nefrens" = Chesapecten (Chesapecten) nefrens
"Chesapecten nefrens" = Chesapecten (Chesapecten) nefrens Ward and Blackwlder 1975 scallop
 Ostreida - Malleidae
Isognomon maxillata Lamarck 1819 oyster
 Lucinida - Lucinidae
"Parvilucina crenulatus" = Parvilucina crenulata
"Parvilucina crenulatus" = Parvilucina crenulata Conrad 1840 clam
 Pholadida - Corbulidae
"Caryocorbula inaequalis" = Corbula inaequalis, Bicorbula idonea
"Caryocorbula inaequalis" = Corbula inaequalis Say 1824 clam
Bicorbula idonea Conrad 1833 clam
 Cardiida - Lasaeidae
Aligena aequata Conrad 1843 aligena
 Cardiida - Veneridae
Macrocallista marylandica Conrad 1833 venus clam
Dosinia acetabulum Conrad 1832 venus clam
 Cardiida - Mactridae
Spisula subparilis, "Spisula subponderosa" = Mactrodesma subponderosa
Spisula subparilis Conrad 1841 clam
"Spisula subponderosa" = Mactrodesma subponderosa d'Orbigny 1852 clam
 Cardiida - Cardiidae
"Cerastoderma laqueatum" = Chesacardium laqueatum
"Cerastoderma laqueatum" = Chesacardium laqueatum Conrad 1830 cockle
 Cardiida - Semelidae
Semele ? carinata Conrad 1830 clam
 Carditida - Astartidae
Astarte thisphila Glenn 1904 clam
 Carditida - Crassatellidae
"Eucrassatella turgidulus" = Marvacrassatella turgidula
"Eucrassatella turgidulus" = Marvacrassatella turgidula Conrad 1843 clam
Scaphopoda
 Gadilida - Gadilidae
Cadulus newtonensis Meyer and Aldrich 1886 tusk shell
Malacostraca
 Decapoda -
Decapoda indet. Latreille 1802 decapod
Thecostraca
 Balanomorpha - Balanidae
"Balanus concavus" = Concavus concavus
"Balanus concavus" = Concavus concavus Bronn 1831 barnacle