Title

Reproduction, development and parental care in two direct-developing flatworms (Platyhelminthes : Polycladida : Acotylea)

Abstract

Variations in reproductive modes, egg production, and the effects of parental care on hatching success are compared between Pleioplana atomata and Imogine zebra. Pleioplana atomata transfers sperm via true copulation, whereas I. zebra dermally impregnates spermatophores onto the dorsal surface of partners. Pleioplana atomata lays up to 750 large eggs over a 6-week period, and I. zebra individuals lay up to 1346 small eggs in 12 days. Female fecundity is positively correlated with body size in both species. Developmental time lines are temperature-dependent, and juvenile worms hatch after 3 and 6 weeks for I. zebra and P. atomata, respectively. Covering of egg masses by the adult is observed for both species and although this parental care is not necessary for egg development or hatching, it plays a significant role in the hatching success of P. atomata. In I. zebra, parental covering of egg masses may play a role in eggshell development.

Publication Date

1-1-2008

Journal Title

Journal of Natural History

Publisher

Taylor & Francis

Digital Object Identifier (DOI)

10.1080/00222930802262758

Scientific Contribution Number

2359

Document Type

Article

Rights

©2008 Taylor & Francis