The reproductive biology of Typosyllis pulchra from the coast
of Washington has been investigated based on observations of animals in the
field and stolonization in the laboratory by both field-collected and cultured
animals. Like most Syllinae, T. pulchra reproduces by stolonization, i.e., each
individual produces 3-4 posterior, detachable, gamete-bearing stolons during
consecutive 30-day intervals. Although some regenerating segments are incorporated
into the stolons, in this species new stolons consist primarily of
stock body segments. Reproductive animals occur in the field from late
January through July; maximum reproductive activity is between April and
June. Long days apparently promote reproduction, but lunar synchronization
of spawning could not be demonstrated.
Larval development is described based on light and scanning electron
microscopy. Fertilization is external; developing larvae settle within 75 hr. The
development of cephalic structures (eyes and antennae) is precocious compared
to other Syllinae that have been studied, and the sequence of parapodium
formation is unusual
