Plum Point, south, Zone 10 (Miocene of the United States)

Where: Calvert County, Maryland (38.6° N, 76.5° W: paleocoordinates 38.8° N, 72.6° W)

• coordinate estimated from map

When: Plum Point Member (Calvert Formation), Burdigalian (20.4 - 16.0 Ma)

• Strontium dating indicates the age of bed 10 to be 16.2–15.8 Ma, or possibly somewhat older (16.4 Ma) [48, 49]. (Marx & Fordyce, 2015)

• bed-level stratigraphic resolution

Environment/lithology: estuary or bay; sandstone

• sparse molluscs, low in diversity; subtropical environment in embayment and dry onshore; area not far from shore, bay, short-term eustatic transgression events, long-term regression trend

Size class: macrofossils

Preservation: original phosphate

Reposited in the USNM

Collection methods: surface (in situ),

Primary reference: C. R. Eastman. 1904. Systematic Paleontology: Pisces. Maryland Geological Survey Miocene, Text 71-93 [M. Uhen/M. Uhen/M. Uhen]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 48884: authorized by Mark Uhen, entered by Mark Uhen on 03.04.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

 Globigerinaceae - Globigerinidae
Globigerinoides sicanus4 de Stefani 1952
Globigerina praebulloides4 Blow 1959
subspecies pseudociperoensis
Globoquadrina altispira4 Cushman and Jarvis 1936
subspecies altispira
 Carditida - Astartidae
Astarte cuneiformis7 Conrad 1840 clam
 Squatiniformes - Squatinidae
Squatina occidentalis n. sp. Eastman 1904 angel shark
 Odontaspidida - Carcharodontidae
"Oxyrhina hastalis" = Cosmopolitodus hastalis
"Oxyrhina hastalis" = Cosmopolitodus hastalis Agassiz 1843 elasmobranch
 Lamniformes - Otodontidae
"Carcharodon megalodon" = Otodus megalodon
"Carcharodon megalodon" = Otodus megalodon Agassiz 1843 megalodon
Also studied in Pimiento et al. 2010
 Lamniformes - Lamnidae
"Oxyrhina desorii" = Isurus oxyrinchus, "Oxyrhina sillimani" = Isurus sillimanii, "Odontaspis cuspidata" = Lamna cuspidata7
"Oxyrhina desorii" = Isurus oxyrinchus Rafinesque 1810 mako shark
"Oxyrhina sillimani" = Isurus sillimanii Gibbes 1847 mako shark
"Odontaspis cuspidata" = Lamna cuspidata7 Agassiz 1843 mackerel shark
 Lamniformes - Odontaspididae
"Odontaspis elegans" = Odontaspis macrota, Carcharias collata n. sp.
"Odontaspis elegans" = Odontaspis macrota Agassiz 1843 sand tiger shark
Carcharias collata n. sp. Eastman 1904 sand shark
 Carchariniformes - Carcharhinidae
Galeocerdo contortus7 Gibbes 1848 tiger shark
 Carchariniformes - Hemigaleidae
"Hemipristis serra" = Hemipristis heteropleurus7
"Hemipristis serra" = Hemipristis heteropleurus7 Agassiz 1844 ground shark
 Tetraodontiformes - Molidae
Ranzania sp.7 Nardo 1840
 Testudines -
"Chelonia indet." = Testudines7
"Chelonia indet." = Testudines7 Batsch 1788 turtle
 Sirenia - Dugongidae
? Nanosiren sp.2, "Metaxytherium calvertense n. sp." = Metaxytherium crataegense5
? Nanosiren sp.2 Domning and Aguilera 2008 dugong
"Metaxytherium calvertense n. sp." = Metaxytherium crataegense5 Simpson 1932 dugong
 Perissodactyla - Equidae
Archaeohippus sp.3 Gidley 1906 anchitheriine horse
 Carnivora - Amphicyonidae
Amphicyon sp.7 Lartet 1836 bear-dog
 Carnivora - Canidae
"Tomarctus marylandica n. sp." = Cynarctus marylandica1
"Tomarctus marylandica n. sp." = Cynarctus marylandica1 Berry 1938 bone-crushing dog
 Ungulata - Tayassuidae
Desmathyus sp.7 Matthew 1907 peccary
 Cetacea -
Parietobalaena palmeri7 Kellogg 1924 whale
Siphonocetus priscus7 Leidy 1851 whale
 Cetacea - Platanistidae
Zarhachis sp.7 Cope 1868 toothed whale
 Cetacea - Physeteridae
Physeterula sp.7 Van Beneden 1877 sperm whale
Orycterocetus crocodilinus7 Cope 1867 sperm whale
 Cetacea - Kentriodontidae
Kentriodon pernix7 Kellogg 1927 toothed whale
 Cetacea - Eurhinodelphinidae
Schizodelphis barnesi6, Schizodelphis sulcatus6, "Eurhinodelphis bossi" = Xiphiacetus bossi7, "Eurhinodelphis vaughni" = Xiphiacetus bossi7, Eurhinodelphis sp.7
Schizodelphis barnesi6 Myrick 1979 toothed whale
Schizodelphis sulcatus6 Gervais 1853 toothed whale
"Eurhinodelphis bossi" = Xiphiacetus bossi7 Kellogg 1925 toothed whale
"Eurhinodelphis vaughni" = Xiphiacetus bossi7 Kellogg 1925 toothed whale
Eurhinodelphis sp.7 Van Beneden and Gervais 1880 toothed whale