''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 may be any of more than one hundred species of semiterrestrial marine crabs in the family Ocypodidae, well known for their sexual dimorphism, sexually dimorphic claws; the males' major claw is much larger than th ...

that is found from

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

to the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

. 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 environment ...

mud-flats Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal fl ...

, and can be extremely abundant. It can be differentiated from the morphologically similar ''

Minuca pugnax ''Minuca pugnax'', commonly known as the Atlantic marsh fiddler crab, is a species of fiddler crab that lives on north-western shores of the Atlantic Ocean. Distribution ''Minuca pugnax'' is the most common species of fiddler crab on the east co ...

'' 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 The fiddler crab or calling crab may be any of more than one hundred species of semiterrestrial marine crabs in the family Ocypodidae, well known for their sexually dimorphic claws; the males' major claw is much larger than the minor claw, whil ...

'', 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 adult ...

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

Description

The

carapace A carapace is a Dorsum (biology), 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 tor ...

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. 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 ''

'' 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 and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

and in the

, having been found as far north as

and as far south as

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

and

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

. This species has also reportedly been found in the

Bahamas The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to ...

. 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 A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at ...

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 Crustaceans of the Atlantic Ocean Crustaceans described in 1802