Zebrida

Zebrida is a small genus of distinctive striped crabs, known as zebra crabs, that live in association with sea urchins in the Indo-Pacific.

Zebrida
Zebrida adamsii
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Brachyura
Family:	Pilumnidae
Subfamily:	Eumedoninae
Genus:	Zebrida White, 1847
Species [1]
Z. adamsii White, 1847 Z. brevicarinata Ng & D. G. B. Chia, 1999 Z. longispina Haswell, 1880

Description

Zebrida was described by Arthur Adams as "a torpid, though elegant little crustacean".^[2] It is "the most unusual" of the genera in the subfamily Eumedoninae, with long spines projecting from the body, and a distinctive pattern of stripes across the exoskeleton.^[3]

Taxonomy and distribution

The genus was thought to be monotypic for a long time, but in 1999, Peter Ng & Diana Chia recognised two additional species, bringing the total number to three.^[3]

• Zebrida adamsii is widespread in the Indian Ocean and western Pacific Ocean, from Japan to Australia.
• Zebrida brevicarinata is only known from Western Australia.
• Zebrida longispina is only known from Western Australia.

Ecology and life cycle

Crabs of the genus Zebrida live, often in pairs, in association with sea urchins,^[4] including Toxopneustes pileolus, Toxopneustes elegans, Tripneustes gratilla, Diadema setosum, Asthenosoma ijimai, Salmacis bicolor, Salmacis virgulata, Heliocidaris crassispina, Pseudocentrotus depressus and a species of Acanthocidaris.^[3][5]

Z. adamsii passes through four zoeal phases, and one megalopa phase before reaching the mature condition.^[6]