About Mithraculus sculptus (Lamarck, 1818)
Mithraculus sculptus is a small crab that has a longer-than-wide carapace and large chelae, or claws. Its carapace is flat, shiny, green, and finely sculpted, with whitish material stuck to its projections. The green chelae are spoon-shaped with white tips. The walking legs are paler in color, hairy, and often covered in encrustations. This species reaches a length of around 4 cm (1.6 in). Mithraculus sculptus is native to the Caribbean Sea and Gulf of Mexico. Its range stretches from the Bahamas and southern Florida to northern Brazil, and it occurs at depths down to about 54 metres (177 ft). It can be found in a variety of different habitats, and it is likely most abundant in back reef environments. This crab is sometimes kept in reef aquaria, and it is reported to be compatible with other reef species. It feeds on algae including bubble algae (Valonia ventricosa), and will also eat any leftover meaty foods; if underfed, it may eat coral polyps or small fish. Research shows Mithraculus sculptus can be used to control excessive bubble algae growth in aquaria. The best control results occur when the crab's diet is supplemented with mysids, rather than pelleted food. This crab also has strong legs, which makes it hard to remove from an aquarium.
