Spanner crab

Spanner crab (Ranina ranina), also known as the frog crab or kona crab, is a species of edible crab found in the waters of the Pacific and Indian Oceans. It is a commercially important species, particularly in Australia and Japan, and is known for its unique shape and sweet, delicate flavor.

Description

The spanner crab is easily recognizable due to its long, slender claws, which resemble the shape of a spanner, hence its common name. The body of the spanner crab is oval and flattened, with a bright red to orange coloration. Adult spanner crabs can reach a carapace width of up to 15 cm and a weight of up to 1 kg.

Distribution and habitat

Spanner crabs are found in the tropical and subtropical waters of the Pacific and Indian Oceans, from Japan to Australia and from East Africa to the Fiji islands. They inhabit sandy or muddy bottoms, usually at depths of 10 to 70 meters, although they have been found at depths of up to 100 meters.

Diet

The diet of the spanner crab consists mainly of small benthic organisms, including mollusks, crustaceans, and worms. They are also known to scavenge on dead animals.

Commercial importance

Spanner crabs are commercially fished in several countries, particularly in Australia and Japan. In Australia, the spanner crab fishery is one of the most important fisheries on the east coast, with the majority of the catch being exported to Asia. The crabs are caught using tangle nets or traps.

Culinary use

The meat of the spanner crab is highly prized for its sweet, delicate flavor and firm texture. It is often used in sushi and sashimi, as well as in various cooked dishes. In Australia, spanner crab is often served in salads or as a main course, while in Japan it is a popular ingredient in tempura.

Conservation status

The spanner crab is not currently considered to be at risk of extinction. However, overfishing and habitat degradation pose potential threats to the species. In Australia, the spanner crab fishery is managed through a combination of size limits, gear restrictions, and closed seasons to ensure the sustainability of the population.