''Minuca minax'', commonly known as the red‐jointed fiddler crab or brackish-water fiddler crab, 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 in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

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 is one of the most common macroinvertebrates in

salt marshes A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open Seawater, saltwater or brackish water that is regularly flooded by the ti ...

in these states. It prefers areas of lower salinity than other fiddler crabs, and can be found in great numbers along the banks of tidal streams, even at distances greater than from the sea. ''Minuca minax'' was formerly in the genus '' Uca'', but in 2016 it was placed in the genus '' Minuca'', a former subgenus of ''Uca''.

Description

Like other fiddler crabs, ''Minuca minax'' males have one

claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or Arthro ...

that is significantly larger than the other, while females have two equal-sized smaller claws. The joints on the claws are red, a noticeable feature that is the origin of the common name "red‐jointed fiddler crab".

Reproduction

''Minuca minax'' breed for two weeks in the summer in a small round burrow dug by the male. The

larvae A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect developmental biology, development such as insects, some arachnids, amphibians, or cnidarians typical ...

are unable to survive in the lower-salinity

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

water preferred by adults, and the adults do not travel to the sea to release the larvae. As such, the larvae use ebb tides to travel to higher-salinity environments to develop before returning as adults.

References

{{Taxonbar, from=Q4477840 Ocypodoidea Crabs of the Atlantic Ocean Crustaceans described in 1855 Taxa named by John Eatton Le Conte