Dickerson Coquina Pits (Pleistocene of the United States)

Where: St. Lucie County, Florida (27.5° N, 80.5° W: paleocoordinates 27.5° N, 80.5° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Okeechobee Formation, Middle Pleistocene (0.8 - 0.1 Ma)

• The vertebrate fossil layer at DCP lies just below the Anastasia Formation and was the lowest stratum regularly exposed above water. While its lower boundary was not measured, this layer was only a few meters thick (Herrera et al., 2006). Electron spin resonance optical dating has confirmed these suspicions; a sample of siliciclastic sediments from just above the vertebrate fossil layer, at a depth of 11.5 m, was dated at 730-430 ka (0.73-0.43 Ma; Burdette et al., 2013). Strata below the vertebrate fossil layer occasionally were exposed at DCP. Petuch (2004) measured some sections and believed that these lower layers corresponded to the late Pliocene to early Pleistocene Nashua ‘formation.’ Burdette et al. (2013) dated a sample from those low layers (depth 14 m) at 1.37-0.61 Ma. If these age assessments are correct, then the fossil layer is certainly older than typical facies of the Anastasia Formation and should be included in Scott’s Okeechobee Formation.

Environment/lithology: mire or swamp; unlithified sandstone

• A drowned tidal creek or marsh covered during an interglacial marine transgression, perhaps during the high sea level stand of 10+ m at ca. 400 ka (Marine Isotope Stage 11)

Size class: macrofossils

Primary reference: J. A. Kilmer and D. W. Steadman. 2016. A middle Pleistocene bird community from Saint Lucie County, Florida. Bulletin of the Florida Museum of Natural History 55:1-38 [M. Clapham/M. Clapham]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 195048: authorized by Matthew Clapham, entered by Matthew Clapham on 14.07.2018, edited by Mark Uhen

Creative Commons license: CC BY (attribution)

Taxonomic list

Aves
 Gruiformes - Gruidae
Grus sp. Brisson 1760 crane
 Gruiformes - Rallidae
Fulica americana Gmelin 1789 American coot
Rallus elegans Audubon 1834 king rail
 Strigiformes - Strigidae
Bubo virginianus Gmelin 1788 great horned owl
 Anseriformes - Anatidae
Aythya collaris Donovan 1809 ring-necked duck
Bucephala clangula Linnaeus 1758 common goldeneye
Anas sp. Linnaeus 1758 dabbling duck
Anas cf. platyrhynchos or rubripes
 Suliformes - Anhingidae
Anhinga anhinga Linnaeus 1766 anhinga
 Suliformes - Sulidae
Morus bassanus Linnaeus 1758 northern gannett
 Suliformes - Phalacrocoracidae
Phalacrocorax cf. auritus Lesson 1831 double-crested cormorant
 Ciconiiformes - Ciconiidae
Ciconia maltha Miller 1910 asphalt stork
 Pelecaniformes - Threskiornithidae
Eudocimus albus Linnaeus 1758 White ibis
 Pelecaniformes - Ardeidae
Ardea herodias Linnaeus 1758 great blue heron
Nyctanassa violacea Linnaeus 1758 yellow-crowned night heron
 Procellariiformes - Diomedeidae
Phoebastria cf. albatrus Pallas 1769 short-tailed albatross
 Galliformes - Phasianidae
Meleagris cf. gallopavo Linnaeus 1758 wild turkey
 Charadriiformes - Alcoidae
Pinguinus impennis Linnaeus 1758 Great auk
Mammalia
 Rodentia - Castoridae
Castoroides dilophidus Martin 1969 giant beaver