Pineapple Sea Cucumber

Overview

The Pineapple Sea Cucumber (Thelenota ananas) is a large, distinctive echinoderm widely distributed across the tropical Indo-Pacific, including the Red Sea and the Great Barrier Reef. It plays a vital role in marine ecosystems by recycling nutrients and maintaining the health of the seabed through its feeding habits.

Appearance

This species is easily recognized by its firm, cylindrical body, which can reach lengths of up to 80 cm. Its surface is covered in numerous large, pointed, star-shaped papillae (teats) often arranged in groups of two or three. The body typically displays warm color tones, ranging from reddish-orange to brown, often marked with darker patches and linear patterns. The ventral side is flat and equipped with numerous tube feet used for locomotion.

Biology & behavior

As a slow-growing, benthic organism, this sea cucumber is typically found in low densities on sandy bottoms or near coral rubble. It is a diurnal species that may host commensal organisms, such as small fish from the Carapidae family or various crustaceans, which find shelter within its body or among its papillae. When threatened, it can perform evisceration, a defense mechanism where it expels its internal organs to deter predators, which it is capable of regenerating over time.

Feeding

This species is a deposit feeder that moves slowly across the seafloor, ingesting large quantities of sediment. It extracts organic matter, such as dead plankton and plant remains, from the sand and excretes clean, processed sediment, effectively acting as a natural cleaner of the seabed.