| Black finger crab | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Infraorder: | Brachyura |
| Family: | Oziidae |
| Genus: | Ozius |
| Species: | O. deplanatus |
| Binomial name | |
| Ozius deplanatus | |
| Synonyms [1] | |
Xantho deplanatusWhite, 1847 | |
Ozius deplanatus, commonly known as the black finger crab and the iron crab, is a species of crab found in New Zealand and Australia. [2] [3]
It is common around the North Island of New Zealand. [2] Found in Australia from Eastern Victoria to New South Wales, on Flinders Island and the Kent Group. [3] [4] It is also found on Lord Howe Island and Norfolk Island. [4]
O. deplanatus is found under boulders and among stones in the lower to mid tidal regions of the intertidal zone on sheltered rocky and gravel shores. [2] [5] [6]
It is distributed sparsely, with one individual per 5 m2. [2]
Adults average 57 mm (2.2 in) in size with a flattened oval-shaped carapace that is wide in the front with blunt lobed edges. This can be a rusty red to chocolate brown colour with light mottling. Underside may be a paler cream colour. [3] The antennae are dark red to brown. Claws are large with a smooth texture. [3] Fingers may be black or brown in colour. [2] Walking legs are pale red with golden setae or hairs. [2]
The black finger crab is a scavenger. [6] It feeds on snails, half-crabs and hermit crabs. It is known to chip away at the shells of larger snails before grasping the animal with its mouth-parts. Smaller snails are crushed by the crab's large claws. It also feeds on limpets and chitons by using the tip of its claw to remove them from a rock. [2]
It will spread its claws when started or threatened. [2]