''Leptuca pugilator'', the sand fiddler crab, Atlantic sand fiddler crab, or Calico fiddler, is a species of

fiddler crab The fiddler crab or calling crab can be one of the hundred species of semiterrestrial marine crabs in the family Ocypodidae. These crabs are well known for their extreme sexual dimorphism, where the male crabs have a major claw significantly l ...

that is found from

Massachusetts Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode ...

to the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

. It lives in burrows in coastal and

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

mud-flats, and can be extremely abundant. It can be differentiated from the morphologically similar '' Minuca pugnax'' and ''

Minuca minax ''Minuca minax'', commonly known as the red‐jointed fiddler crab or brackish-water fiddler crab, is a species of fiddler crab that is found in the United States from Massachusetts to the Gulf of Mexico. It is one of the most common macroinverte ...

'' by the smoothness of the inside of its claws. One claw is larger than the other, and can be much larger than the crab's body, at up to long. ''Leptuca pugilator'' was formerly in the genus '' Uca'', but in 2016 it became a member of the genus ''

Leptuca ''Leptuca'' is a genus of fiddler crabs belonging to the family Ocypodidae. The species of this genus are found on the coasts of the Americas. Description They are small- to large-sized crabs with an adult carapace width of 5–25 mm in adu ...

'', a former subgenus of ''Uca''.

Description

The

carapace A carapace is a dorsal (upper) 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 unde ...

is square in shape, tapering slightly to the rear; it can reach a width of , but is typically up to wide and long. The space between the eyes is much shorter than the

eyestalk In anatomy, an eyestalk (sometimes spelled eye stalk and also known as an ommatophore) is a protrusion that extends an eye away from the body, giving the eye a better field of view. It is a common feature in nature and frequently appears in fict ...

. The males have one extremely enlarged chela (claw), which they use to claim their territory and fight with other males. The claw can be much larger than the body, at up to long, or exceptionally up to long. It is common for males to lose claws in the battles. When this happens, the claw regenerates and the opposite side begins to enlarge. Fiddler crabs are right or left clawed. The inside of these claws are also very smooth, unlike its other close relatives '' Minuca pugnax'' and ''

''.

Geographic distribution

''Leptuca pugilator'' is one of only five species of

s found primarily in temperate areas. The species occurs on the east coast of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

and in the

, having been found as far north as

and as far south as

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

and

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

. This species has also reportedly been found in the

Bahamas The Bahamas, officially the Commonwealth of The Bahamas, is an archipelagic and island country within the Lucayan Archipelago of the Atlantic Ocean. It contains 97 per cent of the archipelago's land area and 88 per cent of its population. ...

. They may also be found in the warmer waters of the Atlantic along the West coast of Africa.

Habitat

''Leptuca pugilator'' can be found in estuarine and coastal areas or sheltered shores with sandy or muddy substrates. It is frequently found in areas bordering

marsh In ecology, a marsh is a wetland that is dominated by herbaceous plants rather than by woody plants.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p More in genera ...

es and along the banks of tidal streams. It can be found in these areas in large numbers – thousands to millions.

References

{{Taxonbar, from=Q2723510 Ocypodoidea Crabs of the Atlantic Ocean Crustaceans described in 1802