Chesapecten

Last updated

Chesapecten
Temporal range: 20.4–0.7  Ma
O
S
D
C
P
T
J
K
Pg
N
Early Miocene to Early Pleistocene
Chesapecten Jeffersonius Outside.jpg
Chesapecten jeffersonius (outside)
Chesapecten Jeffersonius Inside.jpg
Chesapecten jeffersonius (inside)
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Pectinida
Family: Pectinidae
Genus: Chesapecten
Type species
Chesapecten nefrens
Ward & Blackwater, 1975

Chesapecten is an extinct genus of scallop known from marine strata from the early Miocene to the early Pleistocene of the Eastern United States. [1]

Contents

It flourished in the shallow seas along the Mid-Atlantic during this period. Other scallops lived at the same time, but Chesapectens were the most abundant.

Physical Description

Like some other large scallops, the shells of Chesapecten are characterized by a pattern of wide ribs which radiate outward from the apex of the shell. A distinctive feature of Chesapecten is that the radial ribs on its shell are crossed by much smaller, rough, concentric ribs, which follow the contours of the edges of the shell (are "conmarginal"). The left valve of Chesapecten is more convex than the right valve. The adductor muscle scar is large and rounded.

Distribution

The geographical distribution of Chesapecten is limited to the Atlantic coastal plain of North America, [2] where it can be found as far south as Florida, and as far north as Delaware. [3]

One species of Chesapecten, Chesapecten jeffersonius , is the state fossil of Virginia. [4]

History of the taxonomy

Chesapecten was the first genus of North American fossil to be described and illustrated; a drawing of C. jeffersonius appeared in English naturalist Martin Lister's Historiae Conchyliorum, Liber III in 1687. However, Lister did not give Chesapecten its name. [2] Chesapecten was formally named in 1975 by the paleontologists Ward and Blackwater. In 1980, it was assigned to the family Pectinidae by Harold E. Vokes. [1] The name Chesapecten comes from the Chesapeake Bay, where eroding cliffs and outcrops along the beaches regularly expose specimens. [2]

Chesapecten, barnacles and sponge borings (Entobia) from the Pliocene of York River, Virginia. Chesapecten barnacles Pliocene VA.jpg
Chesapecten, barnacles and sponge borings ( Entobia ) from the Pliocene of York River, Virginia.

Habitat and behavior

Chesapecten lived on the seabed in coastal waters ranging in depth from a few feet to 130 feet. When not moving, it is assumed to have rested its flatter right valve on the seafloor. It is very likely that Chesapecten could move suddenly to escape a predator by flapping its valves and using the resulting jet propulsion, in a manner similar to that of almost all living scallops. [2]

Species

Chesapecten jeffersonius fossil at the Tellus Science Museum Chesapecten jeffersonius fossil, Tellus Science Museum.jpg
Chesapecten jeffersonius fossil at the Tellus Science Museum

Different species dominated during different intervals of time: middlesexensis during the Miocene (Eastover Formation); Chesapecten jeffersonius during Early Pliocene (Lower Yorktown Formation, about 4.5 to 4.3 million years ago); and madisonius during Late Pliocene time (Upper Yorktown Formation, about 4 to 3 million years ago).

Species in the genus Chesapecten include:

Related Research Articles

<span class="mw-page-title-main">Loon</span> Family of birds

Loons or divers are a group of aquatic birds found in much of North America and northern Eurasia. All living species of loons are members of the genus Gavia, family Gaviidae and order Gaviiformes.

<span class="mw-page-title-main">Scallop</span> Common name for several shellfish, many edible

Scallop is a common name that encompasses various species of marine bivalve mollusks in the taxonomic family Pectinidae, the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related families within the superfamily Pectinoidea, which also includes the thorny oysters.

<i>Chesapecten jeffersonius</i> Extinct species of bivalve

Chesapecten jeffersonius is the fossilized form of an extinct scallop, which lived in the early Pliocene epoch between four and five million years ago on Virginia's coastal plain. Chesapecten jeffersonius are commonly found in strata exposed along Coastal Plain cliffs along major rivers in southeastern Virginia and eastern North Carolina, and it is the index fossil for the Lower Yorktown Formation.

<i>Argopecten gibbus</i> Species of bivalve

Argopecten gibbus, the Atlantic calico scallop, is a species of medium-sized edible marine bivalve mollusk in the family Pectinidae, the scallops.

<i>Obinautilus</i> Extinct genus of molluscs

Obinautilus is an extinct genus of shelled cephalopod that has been variously identified as an argonautid octopod or a nautilid. It is known from the Late Oligocene to Pliocene of Japan. The shell is discoidal and very involute, with rapidly expanding and compressed whorls, fine radial ribs, a rounded venter with a shallow furrow, and almost closed umbilicus.

<i>Pecten jacobaeus</i> Species of mollusc

Pecten jacobaeus, the Mediterranean scallop, is a species of scallop, an edible saltwater scallop, a marine bivalve mollusc in the family Pectinidae, the scallops.

<i>Kyptoceras</i> Extinct species of mammal

Kyptoceras is a small extinct artiodactyl ungulate mammal of the family Protoceratidae, endemic to southeastern North America from the Miocene to Early Pliocene epoch 23.03—3.6 Ma, existing for approximately 19.43 million years. The species name, amatorum, comes in honor of all amateur fossil collectors, including Frank Garcia the amateur who found it and donated it to the Florida Museum of Natural History.

<i>Hesperotestudo</i> Genus of turtle

Hesperotestudo is an extinct genus of tortoise native to North and Central America from the Early Miocene to the Late Pleistocene. Species of Hesperotestudo varied widely in size, with a large undescribed specimen from the Late Pleistocene of El Salvador reaching 150 cm (4.9 ft) in carapace length, larger than that of extant giant tortoises. Historically considered a subgenus of Geochelone, it is now considered to be distantly related to that genus. Its relationships with other tortoises are uncertain. The exposed areas of the bodies of Hesperotestudo species were extensively covered with large dermal ossicles, which in life were covered in keratin. It has been suggested that species of Hesperotestudo were relatively tolerant of cold weather. Hesperotestudo became extinct at the end of the Pleistocene roughly co-incident with the arrival of the first humans in North America. There is apparently a site in Florida where one individual may have been killed that some suggested were evidence of butchering, although others suggested that the turtle was neither cooked nor does a ledge that was found near it date at the same time as it.

<i>Ontocetus</i> Extinct genus of carnivorans

Ontocetus is an extinct genus of walrus, an aquatic carnivoran of the family Odobenidae, endemic to coastal regions of the southern North Sea and the southeastern coastal regions of the U.S. during the Miocene-Pleistocene. It lived from 13.6 mya—300,000 years ago, existing for approximately 13.3 million years.

<span class="mw-page-title-main">Yorktown Formation</span> Geological Formation in the United States

The Yorktown Formation is a mapped bedrock unit in the Coastal Plain of Maryland, Virginia, North Carolina and South Carolina. It is overconsolidated and highly fossiliferous.

<i>Otodus chubutensis</i> Species of fossil sharks

Otodus chubutensis, meaning "ear-shaped tooth of Chubut", from Ancient Greek ὠτ and ὀδούς – thus, "ear-shaped tooth", is an extinct species of prehistoric megatoothed sharks in the genus Otodus, that lived during Early Miocene to Middle Miocene. The largest individuals were about 13.5 metres (44 ft) long. This shark is considered a close relative of the famous prehistoric megatoothed shark O. megalodon. However, as is the case with O. megalodon, the classification of this species is disputed.

<span class="mw-page-title-main">Ecphora</span> Extinct genus of gastropods

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 of these ocenebrinid murexes are descended from the Eocene murex, Tritonopsis. Ecphoras were indigenous to the North American Eastern Seaboard, being found in marine strata from the Late Eocene until their extinction during the Pliocene. Many ecphora species are important index fossils.

<i>Thecachampsa</i> Extinct genus of reptiles

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 were distinguished primarily by the shape of their teeth, and have since been combined with T. antiquus. More recently erected species were reassigned from other genera, although their assignment to Thecachampsa has since been questioned.

<span class="mw-page-title-main">Antarctic scallop</span> Genus of bivalves

The Antarctic scallop is a species of bivalve mollusc in the large family of scallops, the Pectinidae. It was thought to be the only species in the genus Adamussium until an extinct Pliocene species was described in 2016. Its exact relationship to other members of the Pectinidae is unclear. It is found in the ice-cold seas surrounding Antarctica, sometimes at great depths.

<i>Ecphora</i> (genus) Extinct genus of gastropods

Ecphora is a genus of extinct predatory ocenebrinid murexes indigenous to the North American Eastern Seaboard from Miocene until their extinction during the Pliocene. The common name for this genus and a group of related genera is "ecphora"(s).

Chlamys asper is an extinct species of saltwater scallop, a fossil marine bivalve mollusc in the family Pectinidae, the scallops. This species was described by Sowerby in 1847 under the name Pecten asper. The fossils date from the period of the Pliocene to Pleistocene in Malaysia and Miocene in Indonesia.

<i>Gigantopecten</i> Extinct genus of bivalves

Gigantopecten is a genus of fossil scallops, marine bivalve molluscs in the family Pectinidae, the scallops.

<i>Gigantopecten latissimus</i> Extinct species of bivalve

Gigantopecten latissimus is a species of fossil scallop, a marine bivalve mollusk in the family Pectinidae, the scallops. This species lived during the Miocene and the Pliocene. Fossils have been found in the sediments of France and Spain.

<span class="mw-page-title-main">Calvert Formation</span> Geologic formation in the United States

The Calvert Formation is a geologic formation in Maryland, Virginia, and Delaware. It preserves fossils dating back to the early to middle Miocene epoch of the Neogene period. It is one of the three formations which make up the Calvert Cliffs, all of which are part of the Chesapeake Group.

<i>Adamussium</i> Genus of molluscs

Adamussium is a genus of scallops belonging to the family Pectenidae from the Southern Ocean around Antarctica. There are three known species but only one is extant, the Antarctic scallop. Of the two extinct species A. jonkersi is from the Oligocene deposits on King George Island in the South Shetland Islands and the other, A. necopinatum, was described in 2016 from Pliocene marine deposits in the Vestfold Hills of East Antarctica.

References

  1. 1 2 3 4 5 6 7 8 "Information on Chesapecten from The Paleobiology Database" . Retrieved 2010-09-29.
  2. 1 2 3 4 National Audubon Society Field Guide to North American Fossils, page 465-466, Alfred A. Knopf Publishing New York, ISBN   0-394-52412-8
  3. Goewert, A. E.; Surge, D. (2007). "NASA ADS: Seasonal Variations Preserved in an Extinct Neogene Scallop, Chesapecten, from Florida to Delaware, USA and its Implications for Paleobiogeography". American Geophysical Union. 51. Bibcode:2007AGUFMPP51E..05G.
  4. "The Geology of Virginia". Archived from the original on 2010-05-08. Retrieved 2010-09-29.
  5. 1 2 3 4 "Systematics and biostratigraphy of Chesapecten and Carolinapecten (Mollusca: Bivalvia: Pectinidae) in the upper Miocene and Pliocene "Lower Tamiami Formation" of southwestern Florida" (PDF). Retrieved 2018-08-19.
  6. 1 2 "Bulletin 20: Miocene Fossils of Maryland". Archived from the original on 2010-08-26. Retrieved 2010-09-29.
  7. 1 2 3 "Chesapecten Nefrens - zipcodezoo.com". Archived from the original on 2012-08-20. Retrieved 2010-09-29.

Further reading

Online photo gallery with several pictures of Chesapecten nefrens
Information about Chesapecten from the Global Biodiversity Information Facility
Images of Chesapecten from Google Images