Honeycomb Coral Crab

Trapezia septata is a species of guard crabs in the family Trapeziidae. Like other members of this family, they live in association with corals, feeding on coral tissue and mucus, and defending the corals from predators, like starfish.

Honeycomb pattern over shell and claws. Usually a male and female pair is present, the female the larger of the two.

Carapace length of the male 10.3 mm, breadth 11.9 mm. Quite similar to Trapezia areolata Dana, but differs from it in the following:
1. The network pattern on the carapace with smaller and more meshes.
2. Front narrower and much more produced than the innerorbital tooth, median notch deeper; innerorbital tooth with the anterior margin more convex.
3. Merus of the chelipeds with more obtuse teeth on its anterior margin. Carpus with its inner margin not concave. Palm longer; the movable finger slightly shorter than the dorsal margin of the palm.
4. Tip of the first pleopod of the male with a shorter prolongation and armed with more spines on its inner and outer margins. Telson of female abdomen longer than the sixth segment.

Indo-Pacific: except Hawaiian Islands.