[Summary:]
In spring 1966, 5 species of Polychaetes were collected from masses of squid (
Loligo vulgaris) in the vicinity of Banyuls-sur-Mer (France). Besides single specimens of
Exogone verugera (Claparède),
Lumbrineris impatiens (Claparède),
Megalomma vesiculosum (Montagu) and
Capitella capitata Fabricius, 25 individuaIs of a hitherto
undescribed species of Capitellidae were found. This species is described in detail. It has only 4 segments with setae, all other segments having hooded hooks. Genital hooks may be present or not on the 8th and 9th setigerous segments. The species turned out to be hermaphroditic. It is given the name
Capitella hermaphrodita sp. n. In the laboratory, it had been observed how the animaIs penetrated the squid egg clusters, how they fed and reproduced there. Development of the eggs lasted 5 days till hatching from the egg tube (at 18 - 19 °C). It was tried to rear the trochophores. They showed very little alteration even after having lived in the plancton for several weeks. After infestation by
C. hermaphrodita the egg capsules swell vigorously. Therefore and according to the fact that the animaIs reproduce in the matrix, we conclude that there must be strong relation of
C. hermaphrodita to squid egg cases.