A red, spiny spider crab that fills a crevice by day and walks the rubble after dark.
A heavy-built spider crab with a roughly triangular carapace to about 10 cm across, covered in blunt tubercles and spines, and with a pair of forward-pointing rostral spines separated by a notch — the split brow the genus name refers to. Colour is orange-red to red-brown, often partly hidden by a light covering of sponge and algae around the front margin. The legs are long but thickset for a spider crab. The horned spider crab has far longer and more slender horns and a much smaller body; the decorator crab is smaller again, blunt-snouted and completely buried under its decoration.
By day it wedges into a crevice, under a ledge or inside debris with nothing but the tips of the legs showing, and at night it walks openly across rubble and sand. It is an omnivore and scavenger, taking algae, detritus and dead animals. It decorates only lightly compared with Camposcia, mostly around the rostrum, so the red is generally visible. On a night dive it is one of the crabs seen most reliably on rubble ground.
Majid taxonomy is unsettled and this name is applied broadly across the Indo-Pacific and the Red Sea, almost certainly covering more than one species. Identifications at this level should be treated as provisional rather than firm.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
