The Calvert Formation is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

Virginia Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...

, and

Delaware Delaware ( ) is a state in the Mid-Atlantic region of the United States, bordering Maryland to its south and west; Pennsylvania to its north; and New Jersey and the Atlantic Ocean to its east. The state takes its name from the adjacent Del ...

. It preserves

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

dating back to the early to middle Miocene epoch of the

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

period. The formation is a destination for amateur fossil hunters as well as professional paleontologists. It is one of the three formations which make up the Calvert Cliffs, all of which are part of the

Chesapeake Group The Chesapeake Group is a geologic group in Maryland, Virginia, Delaware, and North Carolina. It preserves mainly marine fossils dating back to the Miocene and Pliocene epochs of the Neogene period. This group contains one of the best studied fos ...

Fossils

The Calvert Formation is extremely fossiliferous. Some of the fossil species represented include the following: Meg_in_gravel

Sharks

* '' Otodus megalodon'' * '' Otodus chubutensis'' * '' Carcharodon hastalis'' * '' Isurus oxyrhincus'' * ''

Physogaleus contortus ''Physogaleus'' is a small genus of prehistoric shark that lived from the Eocene to Miocene epochs. Description ''Physogaleus'' are only known from their fossil teeth and isolated vertebra. It has teeth similar to the modern tiger shark, but sma ...

'' * '' Physogaleus hemmooriensis'' * '' Galeocerdo aduncus'' * ''

Carcharhinus ''Carcharhinus'' is the type genus of the family Carcharhinidae, the requiem sharks. One of 12 genera in its family, it contains over half of the species therein. It contains 35 extant and eight extinct species to date, with likely more species y ...

'' * '' Hemipristis serra'' * '' Squatina sp.'' * ''

Squalus ''Squalus'' is a genus of dogfish sharks in the family Squalidae. Commonly known as spurdogs, these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower jaws similar in size, caudal peduncle with lateral keels; upper pr ...

sp.'' * '' Echinorhinus blakei'' * '' Notorhyncus cepedianus'' * '' Hexanchus gigas'' * ''

Carcharias ''Carcharias'' is a genus of sand tiger sharks belonging to the family Odontaspididae. Once bearing many prehistoric species, all have gone extinct with the exception of the critically endangered sand tiger shark. Description ''Carcharias'' ar ...

'' * '' Carcharoides catticus'' * ''

Isurus retroflexus ''Isurus'' is a genus of mackerel sharks in the family Lamnidae, commonly known as the mako sharks. Description The two living species are the common shortfin mako shark (''I. oxyrinchus'') and the rare longfin mako shark (''I. paucus''). They ...

'' * '' Parotodus benedeni'' * '' Alopias vulpinus'' * ''

Alopias grandis ''Alopias grandis'' is a species of giant thresher shark from the Miocene. Estimates calculated from teeth comparisons suggest the living animal was comparable in size to the extant great white shark. Remains generally consist of teeth, which hav ...

'' * ''

Alopias palatasi ''Alopias palatasi'', commonly referred to as the serrated giant thresher, is an extinct species of giant thresher shark that lived approximately 20.44 to 13.7 million years ago during the Miocene epoch, and is known for its uniquely serrated t ...

'' * ''

Cetorhinus The basking shark (''Cetorhinus maximus'') is the second-largest living shark and fish, after the whale shark, and one of three plankton-eating shark species, along with the whale shark and megamouth shark. Adults typically reach in length. ...

'' * ''

Rhincodon The whale shark (''Rhincodon typus'') is a slow-moving, filter-feeding carpet shark and the largest known extant fish species. The largest confirmed individual had a length of .McClain CR, Balk MA, Benfield MC, Branch TA, Chen C, Cosgrove J, D ...

sp.'' * ''

Negaprion brevirostris The lemon shark (''Negaprion brevirostris'') is a species of shark from the family Carcharhinidae and is classified as a Vulnerable species by the International Union for the Conservation of Nature. Lemon sharks can grow to in length. They are o ...

'' * ''

Rhizoprionodon ''Rhizoprionodon'' is a genus of requiem sharks, and part of the family Carcharhinidae, commonly known as sharpnose sharks because of their long, pointed snouts. Species * '' Rhizoprionodon acutus'' ( Rüppell, 1837) (milk shark) * '' Rhizopri ...

'' * '' Sphryna laevissima'' * ''

Mustelus ''Mustelus'', also known as the smooth-hounds, is a genus of sharks in the family Triakidae. The name of the genus comes from the Latin word ''mustela'', meaning weasel. It should not be confused with the genus name ''Mustela'', which is used ...

sp.'' * '' Scyliorhinidae sp.''

Rays and other cartilaginous fish

* ''

Mobula pectinata ''Mobula'' is a genus of rays in the family Mobulidae that is found worldwide in tropical and warm, temperate seas. Some authorities consider this to be a subfamily of the Myliobatidae (eagle rays). Their appearance is similar to that of manta ...

'' * '' Mobula fragilis'' * '' Mobula loupianensis'' * '' Plinthicus stenodon'' * ''

Rhinoptera ''Rhinoptera'' is a genus of ray commonly known as the cownose rays. This genus is the only member of the family Rhinopteridae. Species There are currently 8 recognized extant (living) species in this genus: * '' Rhinoptera adspersa'' J. P. M� ...

cf. R. studeri'' * ''

Aetobatus arcuatus ''Aetobatus'' is a genus of eagle rays native to the Atlantic, Pacific and Indian Oceans. It was formerly placed in Myliobatidae, but is now placed in its own family Aetobatidae based on salient differences from myliobatids, especially the pecto ...

'' * '' Pteromylaeus sp.'' * '' Dasyatis probsti'' * '' Dasyatis rugosa'' * '' Pristis sp.'' * ''

Edaphodon ''Edaphodon'' was a fish genus of the family Callorhinchidae (sometimes assigned to Edaphodontidae). As a member of the Chimaeriformes, ''Edaphodon'' was a type of rabbitfish, a cartilaginous fish related to sharks and rays. The genus appeare ...

sp.'' * ''

Chimaera Chimaeras are cartilaginous fish in the order Chimaeriformes , known informally as ghost sharks, rat fish, spookfish, or rabbit fish; the last three names are not to be confused with rattails, Opisthoproctidae, or Siganidae, respectively. At ...

sp.''

Bony fish

* ''

Acipenseridae Sturgeon is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous, and are descended from other, earlier acipenseriform fish, which date back to the Early ...

indet.'' * '' Bagre sp.'' * '' Brotula sp.'' * ''

Pogonias ''Pogonias'' is a genus of ray-finned fish in the family Sciaenidae. It was formerly believed to be a monotypic genus only containing the black drum, but a second species was re-described in 2019. Species There are currently two described spec ...

sp.'' * ''

Sciaenops The red drum (''Sciaenops ocellatus''), also known as redfish, channel bass, puppy drum, spottail bass, or simply red, is a game fish found in the Atlantic Ocean from Massachusetts to Florida and in the Gulf of Mexico from Florida to northern Mexi ...

sp.'' * ''

Tautoga The tautoga (pronounced ) is considered the most formal and restrained style of Rotuman dance, usually seen performed in large festivities or ceremonies (called '' kato'aga'', a term summing up all traditional Rotuman ceremonies), or in public opp ...

sp.'' * '' Acanthocybium cf. solandri'' * ''

Thunnus ''Thunnus'' is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, ''Thunnus'' is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also ...

sp.'' * '' Istiophoruscf. platypterus'' * '' Ranzania grahami'' * '' Ranzania tenneyorum'' * '' Ariopsis stauroforus'' * '' Trisopterus sculptus'' * '' Micromesistius cognatus'' * ''

Prionotus ''Prionotus'' is a genus of marine ray-finned fishes belonging to the family Triglidae, one of two genera belonging to the subfamily Prionotinae, the searobins. These fishes are found in the Western Atlantic Ocean and eastern Pacific Ocean, in t ...

'' * ''

Lophius Members of the genus ''Lophius'', also sometimes called monkfish, fishing-frogs, frog-fish, and sea-devils, are various species of lophiid anglerfishes found in the Atlantic and Indian Oceans. ''Lophius'' is known as the "monk" or "monkfish" ...

sp.'' * '' Paralbula dorisiae'' * '' Morone'' * '' Lophokatilus ereboorensis'' * ''

Rachycentron ''Rachycentron'' is the only known member genus of the family Rachycentridae. The genus contains a single living species, the cobia The cobia (''Rachycentron canadum'') is a species of carangiform marine fish, the only extant representativ ...

sp.'' * '' Pomatomus sp.'' * '' Lagodon sp.'' * ''

Micropogonias ''Micropogonias'' is a genus of fish in the family Sciaenidae (Croakers). References

* Sciaenidae Taxa named by Charles Lucien Bonaparte {{Perciformes-stub nl:Knorrepos ...

sp.'' * '' Sphyraena sp.'' * ''

Sarda Sarda may refer to : Places and jurisdictions * Sarda (Albanian Sardë), a ruined ancient town, on Shurdhah Island in northern Albania. * The former Diocese of Sarda, now a Latin Catholic titular see * Sarda river, a river which forms part of t ...

sp.'' * '' Makaira cf. nigricans'' * ''

Chilomycterus ''Chilomycterus'' is a genus of diodontid tetraodontiform fishes commonly called "burrfish." Species There are currently 5 recognized species in this genus:Matsuura, K. (2014): Taxonomy and systematics of tetraodontiform fishes: a review focusi ...

sp.''

Cetaceans

* ''

Aglaocetus ''Aglaocetus'' is a genus of extinct baleen whales known from the Miocene of Patagonia, the US Eastern Seaboard, Japan and the Low Countries. It was once considered a member of Cetotheriidae along with many other putative cetotheres, but was rece ...

sp.'' * Squalodon calvertensis * '' Eurhinodelphis sp.'' * ''

Parietobalaena ''Parietobalaena'' is an extinct genus of baleen whale, belonging to the family Pelocetidae. Fossils are found in Miocene-aged marine strata in North America, Europe, Australia and Japan Japan ( ja, 日本, or , and formally , ''Nihonk ...

palmeri'' * '' Eobalaenoptera harrisoni'' * '' Cephalotrophis coronatus'' * ''

Araeodelphis ''Araeodelphis'' is an extinct genus of river dolphin from the early Miocene of the US Eastern Seaboard.Stephen J. Godfrey; Lawrence G. Barnes; Olivier Lambert (2017). "The Early Miocene odontocete Araeodelphis Natator Kellogg, 1957 (Cetacea; Pl ...

'' * '' Cetotherium'' * '' Zarhachis flagellator'' * '' Pelocetus'' * '' Xiphiacetus''

Pinnipeds

* '' Callophoca obscura''

Crocodilians

* ''

Thecachampsa ''Thecachampsa'' is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from the eastern United States in deposits of Miocene age. Those named in the 19th century we ...

antiquus'' * ''

sericodon''

Invertebrates

* ''

Chesapecten ''Chesapecten'' is an extinct genus of scallop known from marine strata from the early Miocene to the early Pleistocene of the Eastern United States. It flourished in the shallow seas along the Mid-Atlantic during this period. Other scallop ...

nefrens'' * ''

coccymelus'' * ''

Isognomon (For the tree oyster mushroom, see ''Pleurotus ostreatus''.) ''Isognomon'' is a genus of marine bivalve mollusks which is related to the pearl oysters. ''Isognomon'' is known in the fossil record from the Permian period to the Quaternary period ...

sp.'' * ''

Ecphora Ecphora is the common name for a group of extinct predatory marine gastropod mollusks within the family Muricidae, the rocks snails or murexes. The common name is based on the first officially described genus, '' Ecphora''. The entire lineage ...

'' * '' Architectonica trilineata''

Terrestrial mammals

* ''

Cynarctus ''Cynarctus'' is an extinct genus of the Borophaginae subfamily of canids native to North America. The genus was first founded by W. D. Matthew in 1901, based from a pair of lower jaws, ''Cynarctus saxitilis,'' found in the Pawnee Creek Beds of C ...

marylandica'' * ''

Tomarctus brevirostris ''Tomarctus'' is a canid genus of the extinct subfamily Borophaginae which inhabited most of North America during the late Early Miocene to the Early Barstovian age of the Middle Miocene (23—16 million years ago). ''Tomarctus'' existed for ...

'' * ''

Gomphotherium ''Gomphotherium'' (; "welded beast") is an extinct genus of proboscids from the Neogene and early Pleistocene of Eurasia, Africa, North America and Asia. As of 2021, two species, ''G. annectens'' and possibly ''G. subtapiroideum'', are also kno ...

calvertensis'' * ''

Hipparion ''Hipparion'' (Greek, "pony") is an extinct genus of horse that lived in North America, Asia, Europe, and Africa during the Miocene through Pleistocene ~23 Mya—781,000 years ago. It lived in non-forested, grassy plains, shortgrass prairie or st ...

cf. phosphorum'' * ''

Amphicyon ''Amphicyon'' ("ambiguous dog") is an extinct genus of large carnivorous bone-crushing mammals, popularly known as bear dogs, of the family Amphicyonidae, subfamily Amphicyoninae, from the Burdigalian Epoch until the late Pliocene, with the creat ...

cf. frendens'' * ''

intermedius'' * ''

Aphelops ''Aphelops'' (Greek: "smooth" (apheles), "face" (ops), in a reference of lacking a horn) is an extinct genus of hornless rhinoceros endemic to North America. It lived from the Middle Miocene to the early Pliocene, during which it was a common com ...

sp.'' * '' Archaeohippus cf. blackbergi''

Birds

* '' Mergus miscellus'' * '' Morus loxostylus'' * '' Miocepphus''

References

Neogene Maryland Neogene geology of Virginia Neogene Delaware

Fossils

Sharks

Rays and other cartilaginous fish

Bony fish

Cetaceans

Pinnipeds

Crocodilians

Invertebrates

Terrestrial mammals

Birds

See also

References