Candy Stripe Flatworm

Overview

The Candy Stripe Flatworm (Prostheceraeus vittatus) is a striking marine polyclad flatworm known for its distinctive black and white striped pattern. It is commonly found in the waters of the Northeast Atlantic, the English Channel, and the Mediterranean Sea.

Appearance

This species features an elongated, leaf-shaped body that is typically off-white, cream, or yellowish, covered in numerous thin, dark longitudinal stripes. It possesses two prominent, pointed tentacles at the head, near which small eyespots are often visible. The body is extremely thin and flat, though it may appear slightly thicker toward the center, with delicate, often ruffled edges.

Distribution & habitat

These flatworms inhabit rocky and muddy substrates, frequently residing in rock pools, under stones, or within kelp holdfasts. They are distributed across Western Europe, including the southern and western coasts of the British Isles, and extend into the Mediterranean.

Biology & behavior

Prostheceraeus vittatus moves with a graceful, gliding motion powered by thousands of microscopic cilia on its underside, though it is also capable of swimming through rhythmic, sinuous undulations of its body. As a hermaphrodite, it reproduces through a unique form of internal fertilization involving hypodermic insemination, where individuals pierce one another to exchange gametes. They lay their eggs in gelatinous masses that develop directly into miniature adults.

Feeding

As a carnivore, this flatworm feeds on a variety of small marine organisms. Its diet primarily consists of sea squirts (ascidians), though it also consumes bryozoans, small worms, and crustaceans.