Johnson point, 1 (Pleistocene of the United States)

Also known as JP-1

Where: North Carolina (35.0° N, 77.0° W: paleocoordinates 35.1° N, 76.5° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: James City Formation, Early/Lower Pleistocene (2.6 - 0.8 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: shallow subtidal; fine-grained mudstone

• a lower fine-grained fossiliferous mudstone

Size classes: macrofossils, mesofossils

Collection methods: bulk, sieve,

• We sampled the biostrome and overlying bivalve-rich shell bed by surface picking, and by collecting bulk samples of each type of bedding unit at one site where material was newly exposed and unweathered. Each one-liter sample was washed on a sieve with 2 mm openings; fossils separated from matrix were identified to species if possible, counted, examined for epi- and endobionts, and the dominant species were measured to estimate their size-frequency. More than 17,400 specimens belonging to approximately 80 species, mostly of small mollusks, were recovered in this way. Specimen counts were corrected to reflect original numbers of skeletonized organisms (e.g. 1 gas- tropod apical fragment = 1 individual, 1 bivalve beak fragment = 4 individual, 1 balanid side plate = Q individual, etc.).

Primary reference: W. Miller and J. R. DuBar. 1988. Community replacement of a Pleistocene Crepidula biostrome. Lethaia 21(0024-1164):67-78 [N. Heim/C. Lombardi]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 211029: authorized by Noel Heim, entered by Cole Lombardi on 23.06.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

• Any species with below .5% abundance was not listed
Thecostraca
 Balanomorpha - Balanidae
Balanus spp. Da Costa 1778 barnacle
Gastropoda
 Neogastropoda - Columbellidae
"Anachis lafresnayi" = Cotonopsis (Cotonopsis) lafresnayi, "Anachis obesa" = Parvanachis obesa
"Anachis lafresnayi" = Cotonopsis (Cotonopsis) lafresnayi Fischer and Bernardi 1857 snail
"Anachis obesa" = Parvanachis obesa Adams 1845 snail
 Neogastropoda - Nassariidae
"Nassarius albus" = Nassarius antillarum
"Nassarius albus" = Nassarius antillarum d'Orbigny 1847 snail
 Neotaenioglossa - Calyptraeidae
Crepidula fornicata Linnaeus 1758 slipper shell
 Heterostropha - Pyramidellidae
Boonea seminuda Adams 1839 snail
Bivalvia
 Ostreida - Ostreidae
"Ostrea sculpturata" = Conradostrea sculpturata
"Ostrea sculpturata" = Conradostrea sculpturata Conrad 1840 oyster
 Arcida - Arcidae
Anadara aequicostata Conrad 1845 ark
Represented mostly by juveniles
 Nuculanida - Nuculanidae
Nuculana acuta Conrad 1832 pointed nut clam