Almost all legs, with a long spined rostrum. The eastern Pacific arrow crab, on sponge and under ledges.
Total length to about 3 cm, or 5 cm including the legs. A triangular body drawn out into a long serrated rostrum, pale with dark lines, on slender legs.
Its Atlantic counterpart is nearly identical but the two do not overlap, so ocean basin separates them; this is also the smaller of the two.
Intertidal to a hundred and twenty metres on rock and reef. Nocturnal and territorial, sitting in crevices and under ledges by day. Harmless.
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.
