Arthropoda

Porcellana sayana

(White Polkadot Crab)

1. Out of water (Chris Freeman)

2. Out of water (Chris Freeman)

3. Out of water (Chris Freeman)

4. Out of water (Chris Freeman)

5. Out of water (Chris Freeman)

6. Out of water - image enlarged because it was taken through microscope lens (Leslie Bates)

Size

Carapace Width: 1.2cm (0.6") Carapace Length: 1.4cm (0.7")

Recognition Characters

Carapace is usually a little longer than wide, depressed. Dorsal surface is slightly granulate and has fine dorsal plication along sides. Rostrum is triangular, concave above, tip abruptly decurved, margins spinulate or turberculate. Large tooth borders exterior of each eye. Eyes are well developed. Antennae are long and slender, same length of carapace or longer. Chelipeds are strong and larger than carapace. Finely plicated, exterior smooth in older individuals, may be hairy in younger crabs. Last pair of walking legs are small compared to first 3 sets.

Color

Ground color is bright red to rusty red or brown. All dorsal surfaces and abdomen have irregular pattern of mostly white to creamy or yellowish white circular spots. Some spots near rear center part of carapace may be more longitudinal in shape. Rear legs have banded pattern of white and red.

Habitat & Depth

Found in crevices or clusters of oyster shells, among rocks of jetties, or commensally with hermit crabs. Often inhabit the inside of empty mollusk shells. Shallow water to 92m.

Distribution at GRNMS

Rare. May be found sharing mollusk shells with the hermit crabs Pagarus policaris and Petrochirus diogenes.

Geographic Range

North Carolina south to Brazil, Gulf of Mexico, Caribbean

Behavior & Notes

Synonyms

References