Care
In the wild, the spider-like Arrowhead Crab lives around coral reefs at depths of up to 180 metres (591 feet) where it will often be found close to crevices or sheltering beneath anemones. This semi-aggressive, nocturnal creature moves slowly over corals and algae, feeding on crustaceans and other small invertebrates that it finds. The Arrowhead Crab fares best under reef type conditions, but much caution is advised as these animals can be very predatory towards many other reef inhabitants – tankmates must be chosen very, very carefully. Keep only one specimen per tank unless a known mated pair, as these territorial crabs will fight to the death. Never attempt to house with Boxing Shrimps, Cleaner Shrimps and the like, and definitely not with any feather dusters, ornamental snails, or small docile fishes (which an adult crab will grab at by utilising those long-reaching legs, or when the fish are resting unawares overnight). Arrowhead Crabs rarely bother sessile invertebrates but they can have a deleterious effect on beneficial bristleworms. If bristleworms have reached plague proportions in the reef tank, there are often better ways of controlling them than adding an Arrowhead Crab and thus risking all the other inhabitants. These crabs are opportunistic feeders, so ensure yours is well fed to prevent it from looking elsewhere for nourishment. Kept in the right setting, Arrowhead Crabs are unique and are fascinating creatures to observe; however, as detailed above, they do have some specific requirements. Like other crabs, Arrowheads will occasionally moult as they grow, and during this period they are vulnerable to attack and so tend to hide away until the new exoskeleton hardens. *Never use copper based treatments in the invertebrate aquarium.*
Feeding
Primarily a nocturnal scavenger, although it should be offered small feedings of a variety of prepared foodstuffs throughout the day. Prefers meaty items such as Mysis shrimp, vitamin-enriched brineshrimp, krill, chopped prawns/mussel meat etc. Will eat bristleworms and flatworms. Please be aware of its carnivorous nature!
Breeding
This species has been observed spawning in the home aquarium. However, the tiny planktonic zoea larvae, which have to undergo a series of moults to allow them to grow and mature, have proven extremely challenging to raise to adulthood.
