Plagusiidae
Plagusiidae is a family of spider crabs, decapod crustaceans belonging to the infraorder Brachyura. They are characterized by their flattened carapace, long, slender legs, and often have a distinctive pattern of spines and tubercles. These crabs are mostly found in shallow coastal waters, often inhabiting rocky shores and coral reefs.
Common Names
Plagusiidae are commonly known as spider crabs or flat crabs, reflecting their distinctive appearance. Some species have specific common names depending on their location and appearance, such as the spiny spider crab for Plagusia squamosa.
Characteristics
Members of the Plagusiidae family share several key characteristics:
- Flattened Carapace: Plagusiidae crabs have a broad, flattened carapace that allows them to blend into their surroundings.
- Long, Slender Legs: Their legs are long and slender, giving them a spider-like appearance and enabling them to reach into crevices and over uneven surfaces.
- Spines and Tubercles: Many Plagusiidae species possess prominent spines and tubercles on their carapace and legs, likely for defense and camouflage.
- Small Eyes: Their eyes are relatively small and positioned close together on the dorsal side of the carapace.
- Variable Coloration: Plagusiidae crabs exhibit a wide range of colors, from brown and gray to orange and red, often blending with their environment.
Environment
Plagusiidae crabs are mostly found in coastal waters, especially in shallow areas with rocky shores, coral reefs, and seagrass meadows. They are commonly observed in the intertidal zone, exposed during low tide and retreating into crevices or under rocks during high tide.