Callinectes similis
Encyclopedia
Callinectes similis, sometimes called the lesser blue crab or dwarf crab, is a species
of blue crab
described in 1966.
s with which it swims. Adult males may grow up to a width of 122 millimetres (4.8 in), while females may reach 95 mm (3.7 in).
C. similis is most closely related to Callinectes danae
, a species also found in the Gulf of Mexico
, but whose range
extends as far south as Rio Grande do Sul
, and C. ornatus
, a species found from North Carolina
to Rio Grande do Sul. C. similis is most easily separated from C. danae and C. ornatus by the form of the first and second pleopods in males. It can be told apart from the more distantly related C. sapidus by the number of teeth on the front edge of the carapace
, there being six in C. similis and only two in C. sapidus.
, Caribbean Sea
and Gulf of Mexico
from the United States
to Colombia
. It reaches its northern limit near Delaware Bay
. There has been considerable confusion between the various species of Callinectes
, and it now appears that all individuals reported as C. danae
and C. ornatus
from the Gulf of Mexico (with the exception of parts of Florida
) are actually C. similis.
es and estuaries
, being the dominant crab in open bay
s. The species is limited to salinities
of at least 15‰, and temperature
may also affect reproduction.
The diet of C. similis consists of a variety of foodstuffs, including plant
s, fish
, polychaete
s, other crustacean
s including Farfantepenaeus aztecus and Portunus gibbesii, molluscs
such as Mulinia lateralis, and detritus
.
Spawning
takes place in the spring and fall, with females returning to estuaries to release their eggs. Ovigerous (egg-carrying) females carry an average of more than 250,000 eggs.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of blue crab
Callinectes
Callinectes is a genus of crabs, containing 16 species, including the Atlantic blue crab, C. sapidus:*Callinectes affinis Fausto, 1980*Callinectes amnicola *Callinectes arcuatus Ordway, 1863...
described in 1966.
Description
Callinectes similis is a good swimmer, and its last pereiopods are expanded to paddlePaddle
A paddle is a tool used for pushing against liquids, either as a form of propulsion in a boat or as an implement for mixing.-Materials and designs:...
s with which it swims. Adult males may grow up to a width of 122 millimetres (4.8 in), while females may reach 95 mm (3.7 in).
C. similis is most closely related to Callinectes danae
Callinectes danae
Callinectes danae is a species of swimming crab. The carapace is olive-brown and up to long; the walking legs are blue. The species is common in Brazil and the West Indies....
, a species also found in the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
, but whose range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
extends as far south as Rio Grande do Sul
Rio Grande do Sul
Rio Grande do Sul is the southernmost state in Brazil, and the state with the fifth highest Human Development Index in the country. In this state is located the southernmost city in the country, Chuí, on the border with Uruguay. In the region of Bento Gonçalves and Caxias do Sul, the largest wine...
, and C. ornatus
Callinectes ornatus
Callinectes ornatus is a species of swimming crab in the genus Callinectes. It can be distinguished from the closely related Atlantic blue crab by the presence of six frontal teeth on the carapace, compared with only four for C. sapidus. C. ornatus is also smaller, at a maximum carapace width of...
, a species found from North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
to Rio Grande do Sul. C. similis is most easily separated from C. danae and C. ornatus by the form of the first and second pleopods in males. It can be told apart from the more distantly related C. sapidus by the number of teeth on the front edge of the carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
, there being six in C. similis and only two in C. sapidus.
Distribution
Callinectes similis is found in the Atlantic OceanAtlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
, Caribbean Sea
Caribbean Sea
The Caribbean Sea is a sea of the Atlantic Ocean located in the tropics of the Western hemisphere. It is bounded by Mexico and Central America to the west and southwest, to the north by the Greater Antilles, and to the east by the Lesser Antilles....
and Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
from the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
to Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
. It reaches its northern limit near Delaware Bay
Delaware Bay
Delaware Bay is a major estuary outlet of the Delaware River on the Northeast seaboard of the United States whose fresh water mixes for many miles with the waters of the Atlantic Ocean. It is in area. The bay is bordered by the State of New Jersey and the State of Delaware...
. There has been considerable confusion between the various species of Callinectes
Callinectes
Callinectes is a genus of crabs, containing 16 species, including the Atlantic blue crab, C. sapidus:*Callinectes affinis Fausto, 1980*Callinectes amnicola *Callinectes arcuatus Ordway, 1863...
, and it now appears that all individuals reported as C. danae
Callinectes danae
Callinectes danae is a species of swimming crab. The carapace is olive-brown and up to long; the walking legs are blue. The species is common in Brazil and the West Indies....
and C. ornatus
Callinectes ornatus
Callinectes ornatus is a species of swimming crab in the genus Callinectes. It can be distinguished from the closely related Atlantic blue crab by the presence of six frontal teeth on the carapace, compared with only four for C. sapidus. C. ornatus is also smaller, at a maximum carapace width of...
from the Gulf of Mexico (with the exception of parts of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
) are actually C. similis.
Ecology
C. similis lives in marshMarsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es and estuaries
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
, being the dominant crab in open bay
Bay
A bay is an area of water mostly surrounded by land. Bays generally have calmer waters than the surrounding sea, due to the surrounding land blocking some waves and often reducing winds. Bays also exist as an inlet in a lake or pond. A large bay may be called a gulf, a sea, a sound, or a bight...
s. The species is limited to salinities
Salinity
Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
of at least 15‰, and temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
may also affect reproduction.
The diet of C. similis consists of a variety of foodstuffs, including plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s, fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, polychaete
Polychaete
The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms. More than 10,000...
s, other crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s including Farfantepenaeus aztecus and Portunus gibbesii, molluscs
Mollusca
The Mollusca , common name molluscs or mollusksSpelled mollusks in the USA, see reasons given in Rosenberg's ; for the spelling mollusc see the reasons given by , is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. Mollusca is the largest...
such as Mulinia lateralis, and detritus
Detritus
Detritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
.
Spawning
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
takes place in the spring and fall, with females returning to estuaries to release their eggs. Ovigerous (egg-carrying) females carry an average of more than 250,000 eggs.