Many-lined Nudibranch

Overview

The Many-lined Nudibranch (Chromodoris lineolata) is a vibrant sea slug belonging to the family Chromodorididae. Widely distributed across the tropical Indo-West Pacific, this species is frequently observed on reefs and coral rubble, sometimes appearing in large numbers.

Appearance

This nudibranch features a slender, elongated body typically reaching up to 30 mm in length. Its mantle is primarily black, adorned with dense, fine longitudinal lines that are yellow or whitish in color. A distinctive feature is the broad orange or yellow border around the mantle and foot, which is set apart by a thin black line along its inner edge. The rhinophores and flower-like gills are generally maroon to pinkish and are often speckled with tiny white dots. While most individuals display this dark pigmentation, rare specimens lacking the black ground color may appear white.

Distribution & habitat

Chromodoris lineolata is found throughout the tropical Indo-West Pacific, with records spanning from Australia and Indonesia to the Philippines, Hong Kong, and Japan. It is a marine species commonly encountered in shallow waters, including intertidal pools, living reefs, and areas with coral rubble.

Biology & behavior

As a simultaneous hermaphrodite, this species exhibits typical nudibranch reproductive behaviors. Like other members of its family, it possesses the ability to sequester toxic chemicals from its sponge diet, storing them in specialized mantle glands to deter potential predators. It is often seen crawling along the seafloor and can occasionally be found in groups.

Feeding

This species is a specialized predator that feeds on sponges, specifically those within the family Dysideidae, such as species of the genus Lamellodysidea.