The Flatface Swimming Crab, Flat-browed Crab, scientifically known as Achelous depressifrons, is a fascinating crustacean species found in the marine environments of the Western Atlantic. With its distinctive flattened carapace and impressive size, this crab is a notable inhabitant of various coastal habitats.
Description & Characteristics
The Achelous depressifrons can reach a maximum size of up to 15 centimeters across its carapace. Its flattened shape and slightly depressed brow, giving it the common name “Flat-browed Crab,” are prominent features. The carapace is typically a mottled brown or gray color, helping it blend seamlessly with its surroundings. This crab possesses five pairs of walking legs, the first pair modified into large, powerful claws. It also has a pair of prominent eyes that are situated at the front of the carapace.
Habitat and Occurrence
The Flatface Swimming Crab, Flat-browed Crab, Achelous depressifrons, is commonly found along the sandy and muddy bottoms of shallow coastal waters, typically in depths ranging from 1 to 30 meters. It is a common inhabitant of the Western Atlantic Ocean, particularly along the coasts of the United States and the Gulf of Mexico. The crab’s preference for these habitats suggests its adaptation to a variety of marine zones, including the neritic zone, the area of the ocean that extends from the shoreline to the edge of the continental shelf. Its presence in this zone is likely due to the availability of abundant prey and suitable substrates for burrowing.
Taxonomy
The species Achelous depressifrons belongs to the Class: Malacostraca, Order: Decapoda, and Family: Portunidae. This classification places it within a diverse group of crustaceans, all characterized by their ten legs and distinct body structures. The Portunidae family, commonly known as the swimming crabs, includes species with flattened carapaces and adapted swimming legs. This taxonomic grouping highlights the Achelous depressifrons crab’s evolutionary history and its close relationships with other marine crabs.
Feeding
The Achelous depressifrons is a carnivore and a predatory crab, actively hunting its prey. Its diet consists mainly of smaller crustaceans, mollusks, and other invertebrates found in its habitat. The crab’s powerful claws play a crucial role in capturing and crushing its prey. Its opportunistic nature and predatory behavior are essential for its survival in a competitive marine ecosystem.
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