Pyjama Slug

Overview

The Pyjama Slug (Chromodoris quadricolor) is a striking, brightly colored nudibranch widely recognized for its bold, striped appearance. Native to the Red Sea and parts of the western Indian Ocean, it is a popular subject for underwater photography due to its vivid, high-contrast patterns.

Distribution & habitat

This species is most common in the Red Sea and the northwestern Indian Ocean. It has also been documented in the eastern Mediterranean, likely as a result of Lessepsian migration through the Suez Canal. It typically inhabits hard substrates, such as coral reefs and rocky bottoms, where it can be found at depths ranging from shallow reef flats down to approximately 30 meters.

Appearance

Reaching lengths of up to 5 cm, this nudibranch has a smooth, elongated, and flattened body. Its common name refers to its distinct color palette of black, white, blue, and yellow-orange. The mantle is bordered by a thin white edge, followed by a thicker orange-yellow margin and an inner white band. The central portion of the mantle features longitudinal black stripes alternating with pale, opalescent blue bands. Its rhinophores and feathery branchial plumes are typically a deep orange color.

Biology & behavior

Like other members of the Chromodorididae family, the Pyjama Slug is a hermaphrodite. It utilizes its bright coloration as a form of aposematism—a warning signal to potential predators that it is toxic or unpalatable. It feeds specifically on certain sponges, from which it sequesters toxins to incorporate into its own tissues as a chemical defense mechanism. It uses its rhinophores to detect chemical cues in the water, helping it navigate and locate food or mates.