Lupocyclus rotundatus

Lupocyclus rotundatus is a crab species belonging to the family Portunidae, commonly known as swimming crabs. They are fascinating creatures with distinct characteristics and play a crucial role in their marine environments.

Description & Characteristics

Lupocyclus rotundatus is a distinctive crab species with a robust carapace, which is the hard outer shell that protects its body. Its carapace is typically a reddish-brown color, often with darker markings, and has a somewhat rounded shape, giving it its name “rotundatus.” This species is relatively small in size, with adults typically reaching a maximum carapace width of around 50 mm.

Habitat and Occurrence

Lupocyclus rotundatus prefers sandy and muddy substrates, often residing in shallow coastal waters. It can be found in various marine zones, including the intertidal zone, where it is regularly exposed to air during low tides, and the subtidal zone, which remains submerged even at low tide. This adaptable crab can tolerate a range of depths, typically inhabiting areas from the shoreline to a depth of around 50 meters. It’s a common sight in coastal areas along the western Pacific Ocean, often found in countries like Japan, China, and South Korea.

Taxonomy

Lupocyclus rotundatus is classified within the phylum Arthropoda, the largest animal phylum containing a diverse group of creatures with jointed legs. It is a member of the Class Malacostraca, a diverse group of crustaceans with a prominent carapace. This class includes shrimps, lobsters, crabs, and krill. Lupocyclus rotundatus is further categorized within the Order Decapoda, which encompasses all the familiar ten-legged crustaceans like lobsters, shrimps, and crabs. Within this order, it belongs to the Family Portunidae, a group of swimming crabs known for their flattened bodies and paddle-like fifth pair of legs that aid in their swimming abilities.

Feeding

Lupocyclus rotundatus is an opportunistic omnivore, meaning it feeds on a variety of food sources. Its diet consists primarily of algae, small invertebrates, and decaying organic matter. It plays a crucial role in its ecosystem, contributing to the breakdown of organic matter and the recycling of nutrients.