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General

Much is unknown!

Crabs & Lobsters



Crab Index

Crabs



General

Crabs - general

Carrier Crabs

Coral crabs

Coral Crabs

Coral crabs

Decorator Crabs

Decorator Crabs

Gall Crabs

Decorator Crabs

Land & Sea Crabs

Land & sea crabs

Lobsters

Lobsters

Porcelain Crabs

Lobsters

Round Crabs

Lobsters

Swimming Crabs

Lobsters

A small number of the c. 900 crab & species are commercially very important. Those that live on reefs are less well known, but are very diverse in form and often very cryptic. Little is known of their biology and many new species are awaiting description (over 50 in the Philippines alone).

Crabs in General



The first Box Crab (Calappa calappa) was described from Ambon in 1758. Most species are night active and feed on molluscs, breaking the shells open or prising them apart with their specially adapted claws. They are one of the few crabs that are truely right-handed, an adaptation to feeding on right-handed snails!

Elbow Crabs (Parthenopidae) all hold their very long claw arms at right angles to the body, and bend them at the "elbow" so the claws meet close to the mouth parts. Little is known of their biology.

Purse Crabs earn their name from the large pouch (or "purse") at the rear of the abdomen. They are mostly night active and bury themselves quickly in the sand when threatened.

Arcania cf. sagamiensis
Aulacolambrus hoplonotus
Calappa bicornis
Calappa bicornis
Calappa bicornis
Calappa calappa
Calappa cf. philargius
Cymo sp.?
Gomeza bicornis
Stacks Image 2365
Lambrachaeus cf. ramifer
Lambrachaeus cf. ramifer
Lambrachaeus cf. ramifer
Leuosia cf. pubescens
Leucosia anatum
Leucosia anatum moulting
Pecnon planissimum
Pseudolambrus cf. lobatus
Unidentified
Unidentified

Round Crabs



Round Crabs belong to the Xanthidae, the largest family of crabs. They are encountered in many reef niches, either free-living, hiding between the branches of corals, or half buried in soft coral. They are often brightly coloured, which serves as a warning, as they are very poisonous, producing toxins similar to those found in puffer fish livers. There is no antidote.

Pilumnus sp.
Lybia tesselata
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
Carpilius maculatus

Swimming Crabs



Some swimming crabs are commercially important. Portunus rituberculatus, accounts for a fifth of the global annual catch of crustaceans. Most species are fairly large, swim well and are aggressive hunters. Some of the larger species appear on reefs, but there is a group of small species in the genus Lissocarcinus that live in close association with sea cucumbers and soft corals. They are often overlooked and their lives are little known.

Caphrya sp. 1 in it
Caphrya sp. 1 in it
Caphrya sp. 1 in it
Charybdis acutifrons
Lissocarcinus orbicularis
Lissocarcinus orbicularis
Lissocarcinus laevis
Lissocarcinus laevis
Lissocarcinus laevis with eggs
Lupocyclus sp.
Portunus pelagicus
Portunus pelagicus

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Crabs in General

Crabs in General

The first Box Crab (Calappa calappa) was described from Ambon in 1758. Most species are night active and feed on molluscs, breaking the shells open or prising them apart with their specially adapted claws. They are one of the few crabs that are truely right-handed, an adaptation to feeding on right-handed snails!

Elbow Crabs (Parthenopidae) all hold their very long claw arms at right angles to the body, and bend them at the "elbow" so the claws meet close to the mouth parts. Little is known of their biology.

Purse Crabs earn their name from the large pouch (or "purse") at the rear of the abdomen. They are mostly night active and bury themselves quickly in the sand when threatened.

Arcania cf. sagamiensis
Aulacolambrus hoplonotus
Calappa bicornis
Calappa bicornis
Calappa calappa
Calappa cf. philargius
Gomeza bicornis
Lambrachaeus cf. ramifer
Lambrachaeus cf. ramifer
Leuosia cf. pubescens
Leucosia anatum
Pecnon planissimum
Pseudolambrus cf. lobatus
Unidentified

Round Crabs

Round Crabs

Round Crabs belong to the Xanthidae, the largest family of crabs. They are encountered in many reef niches, either free-living, hiding between the branches of corals, or half buried in soft coral. They are often brightly coloured, which serves as a warning, as they are very poisonous, producing toxins similar to those found in puffer fish livers. There is no antidote.

Pilumnus sp.
Lybia tesselata
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
cf. Cryptodromia sp.
Carpilius maculatus

Swimming Crabs

Swimming Crabs

Some swimming crabs are commercially important. Portunus rituberculatus, accounts for a fifth of the global annual catch of crustaceans. Most species are fairly large, swim well and are aggressive hunters. Some of the larger species appear on reefs, but there is a group of small species in the genus Lissocarcinus that live in close association with sea cucumbers and soft corals. They are often overlooked and their lives are little known.

Caphrya sp. 1 in it
Caphrya sp. 1 in it
crab-swimming-03-Caphrya-sp-1.jpg
Charybdis acutifrons
Lissocarcinus orbicularis
Lissocarcinus orbicularis
Lissocarcinus laevis
Lissocarcinus laevis
Lissocarcinus laevis with eggs
Lupocyclus sp.
Portunus pelagicus
Portunus pelagicus