Portunus pelagicus (Linnaeus, 1758)
Portunus pelagicus, commonly referred to as the blue crab, blue swimmer crab, blue manna crab, and flower crab, belongs to the family of Portunidae . This species of swimming crab is typically found in the Indo-Pacific region.
Current Status of Name :
This name is currently accepted taxonomically.
Rank : Species
Environment : Marine
Taxonomy Classification
- Kingdom : Animalia
- Phylum : Arthropoda
- Class : Malacostraca
- Order : Decapoda
- Family : Portunidae
- Genus : Portunus
- Species : Portunus pelagicus
Portunus pelagicus
Description :
Morphology:
- Carapace (shell): Broad, flattened, and hexagonal in shape, with a distinct ridge across the middle.
- Size: Carapace width typically ranges from 10 to 20 cm (4 to 8 inches).
- Color: Greenish-blue to dark blue or purplish-blue on the carapace and legs.
- Chelipeds (claws): Well-developed, with the right claw typically larger than the left.
- Legs: Five pairs of walking legs, with the last pair flattened and paddle-like for swimming.
- Eyes: Stalked compound eyes on movable eyestalks.
- Mouthparts: Modified appendages used for feeding, including maxillipeds and mandibles.
Anatomy:
- Exoskeleton: A hard, chitinous outer covering that is periodically shed during molting.
- Gills: Feathery structures located in the branchial chambers for gas exchange.
- Digestive system: A simple gut consisting of a short esophagus, stomach, and intestine.
- Reproductive system: Separate sexes, with males having modified appendages for transferring spermatophores.
- Nervous system: A central nervous system with a brain and ventral nerve cord.
Habitat and Distribution:
- Found in the Indo-Pacific region, including the coastal waters of Southeast Asia, Australia, and parts of the eastern Pacific.
- Inhabits shallow coastal waters, such as estuaries, mangrove areas, and near-shore marine environments.
- Tolerant of a wide range of salinities and can enter brackish and even fresh water.
Ecology and Behavior:
- Opportunistic omnivore, feeding on a variety of prey, including bivalves, crustaceans, fish, and plant matter.
- Highly mobile and an excellent swimmer, using its paddle-like rear legs for propulsion.
- Exhibits migratory behavior, moving between coastal and offshore waters for spawning and feeding.
- Females can carry and incubate up to 2 million eggs under their abdomens.
Commercial Importance and Aquaculture:
- Portunus pelagicus is an important commercial and aquaculture species in many parts of its range.
- Highly valued for its meat, which is consumed fresh, frozen, or processed.
- Farming and cultivation of this species are practiced in several countries, including China, India, and Indonesia.
Conservation Status:
- The IUCN Red List has not assessed the global conservation status of Portunus pelagicus.
- However, overfishing and habitat degradation may threaten some local populations.
- Sustainable management practices, including aquaculture, are important for maintaining healthy stocks.
This description covers the key aspects of the blue swimming crab, including its taxonomy, morphology, anatomy, habitat, distribution, ecology, behavior, commercial importance, aquaculture, and conservation status as a crustacean species.