''Chione cancellata'', is a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of medium-sized saltwater

clam Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two sh ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

bivalve Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, biv ...

mollusc in the family

Veneridae The Veneridae or venerids, common name: Venus clams, are a very large family of minute to large, saltwater clams, marine bivalve molluscs. Over 500 living species of venerid bivalves are known, most of which are edible, and many of which are ...

, the venus clams. The species is now understood to be strictly Caribbean in distribution. The more northern species which resembles this, which is usually called the "cross-barred venus" and which was considered to be ''C. cancellata'' for many years, is now known to be ''

Chione elevata ''Chione elevata'', the Florida cross barred venus, is a species of bivalve in the family Veneridae often confused for another species, '' Chione cancellata'' with a more southern distribution. Distribution Native to Florida, and northward to N ...

''.

Shell description

This species grows to be 1 inches across, and has a rounded, triangular shell with both strong concentric ridges and strong radial ribbing, which together form a raised crisscross pattern of ridges, hence the specific name, ''cancellata'' or cancellate. The interior of the shell possesses crenulations on its bottom edge, and like most Veneridae it has well-developed lateral and cardinal teeth on the hinge line. The shell of ''C. cancellata'' ''

sensu stricto ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular c ...

'' is quite brightly colored and patterned. (This is in contrast to the species '' C. elevata'' which usually has a grayish yellow-white exterior, occasionally with a few lavender radial stripes. The shell interior of '' C. elevata'' is usually purple.)

Habitat

The species commonly lives on sandy bottoms of sounds and shallow offshore waters, and the shells are commonly found washed ashore on sound and ocean beaches.

Distribution

This species was, until recently, thought to range from

New Jersey New Jersey is a U.S. state, state in the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. It is bordered on the north and east by the state of New York (state), New York; on the ea ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. It is now known that the Caribbean ''Chione'' is in fact ''C. cancellata'' and the more northern clam is a different species, ''C. elevata''.

Human use

Although this clam is sweeter in taste than the

northern quahog The hard clam (''Mercenaria mercenaria''), also known as the round clam, hard-shell (or hard-shelled) clam, or the quahog, is an edible marine bivalve mollusk that is native to the eastern shores of North America and Central America from Prince ...

, ''

Mercenaria mercenaria The hard clam ('' Mercenaria mercenaria''), also known as the round clam, hard-shell (or hard-shelled) clam, or the quahog, is an edible marine bivalve mollusk that is native to the eastern shores of North America and Central America from Prince ...

'', it is a lot smaller, and is rarely eaten.

Genetic evolution and anatomy

The

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. A ...

status of the common tropical western Atlantic venerid bivalve, ''Chione cancellata'', was radically revised in 2000. What had previously been thought to be one species was discovered to be a "cryptic species pair" and as such it was divided into two separate species, on the basis of morphological, morphometric and phylogenetic analyses. The more colorful Caribbean species is still called ''C. cancellata''. However, specimens inhabiting waters off the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

and

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

south to

Belize Belize (; bzj, Bileez) is a Caribbean and Central American country on the northeastern coast of Central America. It is bordered by Mexico to the north, the Caribbean Sea to the east, and Guatemala to the west and south. It also shares a wa ...

, are in fact a different species. This species was described originally by

Thomas Say Thomas Say (June 27, 1787 – October 10, 1834) was an American entomologist, conchologist, and herpetologist. His studies of insects and shells, numerous contributions to scientific journals, and scientific expeditions to Florida, Georgia, the ...

as ''

''. Examination of specimens of both species supported the separation, including difference in shell

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

, hinge morphology, and size of the pallial cavity. A phylogenetic analysis of extant species failed to define the exact evolutionary history of ''C. cancellata'' and ''C. elevata''. Separation of the two species suggests an ancient faunal division in the western

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...

between the northern Caloosahatchian Province and the southern

Atlantic Gatunian Province The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

. This hypothetical division has been dated back to the Early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Veneridae The Veneridae or venerids, common name: Venus clams, are a very large family of minute to large, saltwater clams, marine bivalve molluscs. Over 500 living species of venerid bivalves are known, most of which are edible, and many of which are ...

References

Phylogenetic Analysis of Chione

Cross Barred Venus Clam
an
NC Sea Grant

External links

Embryonic development and shell differentiation in Chione cancellata
{{Taxonbar, from=Q3016904 Veneridae Molluscs described in 1767 Taxa named by Carl Linnaeus