swimming crab

Thân thiện

A swimming crab scuttles sideways across the sandy ocean floor.

Definition

Noun: 1. A type of marine crab characterized by having some of its legs (typically the last pair of pereiopods) flattened and fringed with hair-like setae, which are adapted for swimming. These crabs are capable of more agile movement in the water compared to typical bottom-walking crabs.

Usage

The term "swimming crab" is used to classify and describe crabs within certain families (like Portunidae) that possess this specific anatomical adaptation. - It functions as a common name for the group and can be used as a countable noun for individual crabs. - Example: "The researcher studied the behavior of the swimming crab." - Example: "We caught several swimming crabs in the net."

Examples

• "The blue crab, a common swimming crab, uses its paddle-like rear legs to propel itself through the water."
• "Unlike many crabs that scuttle along the seafloor, swimming crabs can chase prey in the water column."
• "The fossil record shows that the adaptations of the swimming crab evolved millions of years ago."

Advanced Usage

• The term is often used in marine biology, ecology, and fisheries contexts to distinguish these crabs from other types.
• It can be part of compound names specifying a particular species, e.g., "the common shore swimming crab."

Variants and Related Words

• Portunid crab: The formal biological family name (Portunidae) for most swimming crabs. This is a more scientific synonym.
• Paddle crab: A common name used in some regions, directly referencing the flattened, paddle-shaped legs.

Synonyms

• Portunid crab

Notes on Meaning

• The defining feature is the morphological adaptation of the legs for swimming. Not all crabs that can swim (e.g., by walking underwater) are classified as "swimming crabs."
• The term contrasts with "walking crabs" or "bottom-dwelling crabs," which lack these specialized limbs.

Học thuật

Noun

1. marine crab with some legs flattened and fringed for swimming