Banded Porcelain Crab – Petrolisthes galathinus

The Banded Porcelain Crab, scientifically known as Petrolisthes galathinus, is a small and strikingly patterned crab commonly found in coastal waters. Its distinctive banding and relatively docile nature make it a popular subject for marine enthusiasts.

Description & Characteristics

The Petrolisthes galathinus is a small crab, typically reaching a maximum size of around 2.5 cm in carapace width. Its body is characterized by a broad, flattened carapace, adorned with a series of alternating dark and light bands. These bands, which give the crab its common name, are a key distinguishing feature. The crab’s legs are also banded and are used for both locomotion and feeding. Their small size and distinct banding pattern make them easily recognizable.

Habitat and Occurrence

The Banded Porcelain Crab is commonly found in the intertidal and shallow subtidal zones of rocky shores. They prefer habitats with a combination of gravel soils, rubble rocks, and stony soils, providing shelter and access to their food sources. The Petrolisthes galathinus is typically found in the infralittoral and circalittoral marine zones, which extend from the low tide mark to depths of around 200 meters. This wide range of habitats allows them to thrive in a variety of coastal environments.

Taxonomy

The species Petrolisthes galathinus belongs to the Class: Malacostraca, Order: Decapoda, and Family: Porcellanidae. This classification places it within the diverse group of crustaceans that includes crabs, lobsters, and shrimp. The family Porcellanidae, commonly known as porcelain crabs, is distinguished by their flattened bodies and soft, brittle shells.

Feeding

The Banded Porcelain Crab is an omnivorous feeder, relying on a combination of detritus, filter feeding, and zooplankton for sustenance. They scavenge for food among the rocks and sediment, consuming decaying plant and animal matter. They also utilize their specialized mouthparts to filter small particles of food from the water column. This versatile feeding strategy allows them to adapt to the changing conditions of their diverse coastal habitat.