REPRODUCTION AND LARVAL DEVELOPMENT OFPOLYDORA GIARDIMESNIL (POLYCHAETA: SPIONIDAE)

Abstract

The larval development of P. giardi was described. Adults occur in burrows found in coralline algae and abalone shells. Sexes are separate. Females deposit eggs in hollow, cylindrical capsules attached to the wall of the tube by filaments. Larvae are released from capsules at the 3-setiger stage. Planktonic development exceeds 25 days at 15.degree. C. Larvae settle randomly on the surface of calcareous substrata, and metamorphose in the presence of coralline algae. Only 8.3% of the population were sexually mature over a 6-mo. period from Feb. through July. The larvae of P. giardi closely resemble those of P. flava, P. caeca and P. concharum. This larval resemblance is also reflected in adult morphology.