Plum Point, south, Zone 10: Langhian, Maryland

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Globigerinidae
Globoquadrina altispira (Cushman and Jarvis 1936)
Gibson 1983
recombined as Dentoglobigerina altispira
subspecies altispira
Globigerinoides altiaperturus Boli 1957
Gibson 1983
Globigerinoides sicanus de Stefani 1950
Gibson 1983
recombined as Trilobatus sicanus
Praeorbulina glomerosa
Gibson 1983
Globigerina praebulloides Blow 1959
Gibson 1983
subspecies pseudociperoensis
Bivalvia - Carditida - Astartidae
Astarte cuneiformis Conrad 1840
Uhen 2007 1 specimen
Reptilia - Testudines
Chelonia indet. (Latreille 1800)
Uhen 2007
synonym of Testudines
Mammalia - Sirenia - Dugongidae
? Nanosiren sp. Domning and Aguilera 2008
Domning and Aguilera 2008
Metaxytherium calvertense n. sp. Kellogg 1966
Kellogg 1966 2 specimens
synonym of Metaxytherium crataegense
Mammalia - Carnivora - Amphicyonidae
Amphicyon sp. Lartet 1836
Uhen 2007 1 specimen
Mammalia - Carnivora - Canidae
Tomarctus marylandica n. sp. Berry 1938
Berry 1938 1 specimen
recombined as Cynarctus marylandica
Mammalia - Perissodactyla - Equidae
Archaeohippus sp. Gidley 1906
Gazin and Collins 1950 1 specimen
Mammalia - Cetacea - Platanistidae
Zarhachis sp. Cope 1868
Uhen 2007 1 specimen
Mammalia - Cetacea - Kentriodontidae
Kentriodon pernix Kellogg 1927
Uhen 2007 1 specimen
Mammalia - Cetacea - Eurhinodelphinidae
Eurhinodelphis sp. Van Beneden and Gervais 1880
Uhen 2007
Rhabdosteus hruschkai Myrick 1979
Myrick 1979
    = Schizodelphis barnesi Myrick 1979
Muizon 1988
Schizodelphis morckhoviensis (Du Bus 1872)
Godfrey and Lambert 2023
Rhabdosteus longirsotris
Myrick 1979 1 specimen
    = Schizodelphis sulcatus Gervais 1853
Muizon 1988
Eurhinodelphis bossi Kellogg 1925
Uhen 2007 1 specimen
recombined as Xiphiacetus bossi
Eurhinodelphis vaughni Myrick 1979
Uhen 2007 1 specimen
synonym of Xiphiacetus bossi
Mammalia - Cetacea - Physeteridae
Physeterula sp. Van Beneden 1877
Uhen 2007 1 specimen
Orycterocetus crocodilinus Cope 1867
Uhen 2007 1 specimen
Mammalia - Cetacea
Siphonocetus priscus (Leidy 1851)
Uhen 2007 3 specimens
nomen dubium belonging to Siphonocetes
Parietobalaena palmeri Kellogg 1924
Uhen 2007 3 specimens
Mammalia - Tayassuidae
Desmathyus sp. Matthew 1907
Uhen 2007 1 specimen
Actinopteri - Tetraodontiformes - Molidae
Ranzania sp. Nardo 1840
Uhen 2007 1 element
Chondrichthyes - Squatinidae
Squatina occidentalis n. sp. Eastman 1904
Chondrichthyes - Carcharhiniformes - Hemigaleidae
Hemipristis serra Agassiz 1835
Uhen 2007 1 element
Chondrichthyes - Carcharhiniformes - Carcharhinidae
Galeocerdo contortus Gibbes 1847
Uhen 2007 5 elements
recombined as Physogaleus contortus
Chondrichthyes - Lamniformes - Lamnidae
Oxyrhina desorii Agassiz 1843
synonym of Isurus oxyrinchus
Oxyrhina sillimani Gibbes 1847
recombined as Isurus sillimanii
Oxyrhina hastalis Agassiz 1838
recombined as Carcharodon hastalis
Chondrichthyes - Lamniformes - Odontaspididae
Odontaspis cuspidata (Agassiz 1843)
Uhen 2007 3 elements
recombined as Araloselachus cuspidatus
Chondrichthyes - Lamniformes - Mitsukurinidae
Odontaspis elegans (Agassiz 1838)
synonym of Otodus macrotus
Chondrichthyes - Lamniformes - Otodontidae
Carcharodon megalodon (Agassiz 1835)
recombined as Otodus megalodon
Also studied in Pimiento et al. 2010
Chondrichthyes - Lamniformes - Carchariidae
Carcharias collata n. sp. Eastman 1904
see common names

Geography
Country:United States State/province:Maryland County:Calvert
Coordinates: 38.6° North, 76.5° West (view map)
Paleocoordinates:38.8° North, 73.2° West
Basis of coordinate:estimated from map
Time
Period:Neogene Epoch:Miocene
Stage:Langhian 10 m.y. bin:Cenozoic 5
Key time interval:Langhian
Age range of interval:15.97000 - 13.82000 m.y. ago
Stratigraphy
Geological group:Chesapeake Formation:Calvert Member:Plum Point
Regional section:Shattuck Regional bed:10
Regional order:bottom to top
Stratigraphic resolution:bed
Stratigraphy comments: 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)
Lithology and environment
Primary lithology: sandstone
Includes fossils?Y
Environment:estuary/bay
Geology comments: 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
Taphonomy
Modes of preservation:body,original phosphate
Size of fossils:macrofossils
Disassociated minor elements:some
Collection methods and comments
Collection methods:surface (in situ),field collection
Reason for describing collection:taxonomic analysis
Museum repositories:USNM
Metadata
Database number:48884
Authorizer:M. Uhen, M. Nelson Enterer:M. Uhen, M. Nelson
Modifier:G. Varnham Research group:vertebrate
Created:2005-04-03 12:10:28 Last modified:2022-03-03 04:13:49
Access level:the public Released:2005-04-03 12:10:28
Creative Commons license:CC BY
Reference information

Primary reference:

17219. C. R. Eastman. 1904. Systematic Paleontology: Pisces. Maryland Geological Survey Miocene, Text 71-93 [M. Uhen/M. Uhen/M. Uhen]

Secondary references:

13047 C. T. Berry. 1938. A Miocene dog from Maryland. Proceedings of the United States National Museum 85(3035):159-161 [M. Uhen/M. Uhen/M. Uhen]
14892 L. de Verteuil and G. Norris. 1996. Dinoflagellate cyst zonation and allostratigraphy of the Chesapeake Group. Micropaleontology 42:1-25 [M. Uhen/M. Uhen/M. Uhen]
27454 D. P. Domning and O. A. Aguilera. 2008. Fossil Sirenia of the West Atlantic and Caribbeaan Region. VIII. Nanosiren garciae, gen. et sp. nov. and Nanosiren sanchezi, sp. nov. Journal of Vertebrate Paleontology 28(2):479-500 [M. Uhen/M. Uhen]
13413 C. L. Gazin and R. L. Collins. 1950. Remains of land mammals from the Miocene of the Miocene of the Chesapeake Bay Region. Smithsonian Miscellaneous Collections 116(2):1-21 [M. Uhen/M. Uhen/M. Uhen]
17886 T. G. Gibson. 1983. Key foraminifera from upper Oligocene to lower Pleistocene strata of the central Atlantic coastal plain. Smithsonian Contributions to Paleobiology 53:355-453 [M. Uhen/M. Uhen]
85660 S. J. Godfrey and O. Lambert. 2023. Miocene Toothed Whales (Odontoceti) from Calvert Cliffs, Atlantic Coastal Plain, USA. Smithsonian Contributions to Paleobiology 107:29-186 [M. Uhen/M. Uhen]
14028 R. Kellogg. 1966. New Species of Extinct Miocene Sirenia. United States National Museum Bulletin 247(3):65-98 [M. Uhen/M. Uhen/M. Uhen]
55050 F. G. Marx and R. E. Fordyce. 2015. Baleen boom and bust: a synthesis of mysticete phylogeny, diversity and disparity. Royal Society Open Science 2:140434 [M. Uhen/M. Uhen]
12196 C. Muizon. 1988. Le polyphyletisme des Acrodelphidae, Odontocetes longirostres du Miocene europeen. Bulletin du Muséum National d'Histore Naturelle, Section C Sciences de la Terre, Paleontologie, Geologie, Minerologie 10:31-88 [M. Uhen/M. Uhen/M. Uhen]
15550 A. C. Myrick. 1979. Variation, taphonomy, and adaptation of the Rhabdosteidae (=Eurhinodelphidae) (Odontoceti, Mammalia) from the Calvert Formation of Maryland and Virginia. University of California, Los Angeles 1-411 [M. Uhen/M. Uhen]
38040 C. Pimiento, D. J. Ehret, B. J. MacFadden and G. Hubbell. 2010. Ancient Nursery Area for the Extinct Giant Shark Megalodon from the Miocene of Panama. PloS One 5(5):1-9 [M. Uhen/M. Uhen]
24251 M. D. Uhen. 2007. USNM Chesapeake Group Cetacean Collection Data. [M. Uhen/M. Uhen]
32709 L. W. Ward and G. W. Andrews. 2008. Stratigraphy of the Calvert, Choptank, and St. Marys Formations (Miocene) in the Chesapeake Bay Area, Maryland and Virginia. Virginia Museum of Natural History Memoir 1-169 [M. Uhen/M. Uhen]