Variable Sea Cucumber

Overview

The Variable Sea Cucumber (Holothuria sanctori) is a marine echinoderm characterized by its elongated, cylindrical body and distinct, variable coloration. It is commonly found in the Mediterranean Sea and parts of the temperate Eastern Atlantic, often observed in rocky environments or seagrass meadows.

Appearance

This species typically reaches lengths of 20 to 30 cm with a diameter of approximately 6 cm. Its base color is generally dark brown, though its appearance can vary significantly due to the presence of light-colored, yellowish or white rings that encircle the base of its dorsal papillae. In some individuals, these markings are so prominent that the animal appears much lighter, while others may be almost entirely dark brown.

Biology & behavior

Holothuria sanctori is a nocturnal, solitary species that remains hidden in rocky crevices or under stones during the day. It becomes active after dark to forage. While generally non-territorial, it has been observed displaying aggressive behavior toward other species. It is considered a thermophilic species, meaning it thrives in warmer waters, and its distribution is sometimes monitored as an indicator of rising water temperatures.

Feeding

As a scavenger and deposit feeder, this sea cucumber plays a role in maintaining the cleanliness of its environment. It feeds on detritus, organic debris, and sediment, using its specialized tentacles to collect food particles from the seafloor.