Meeting Abstract

35.1  Jan. 5  Regeneration in benthic ctenophores (Platyctenida) DUBUC, Timothy R; University of Hawaii Manoa dubuc@hawaii.edu

Coeloplana and Vallicula species have a unique derived lifestyle compared to their pelagic relatives, including: a benthic habitat, loss of ctene rows, and a flattened oral/aboral body. Adult benthic ctenophores have a complex gastrovascular system laced with a rich fibrous network of muscle throughout their body. During asexual reproduction, an individual either buds a small peripheral portion of its body that eventually develops into a complete cloned adult, or divides in half, creating a new individual. This study uses confocal microscopy to track the development and reorganization of muscle fibers as well as the gastrovascular system through each mode of asexual reproduction. In development of a new asexually produced individual, the wounded side fuses together, and then tissue reorganization occurs. In budded individuals, the wounded side is where the first tentacle develops, followed by the development a complex gastrovascular system, a pharynx for feeding as well as a statocyst. Individuals that undergo transverse fission simply have to close the wounded area, and reconstruct the gastrovascular system while building a second tentacle and statocyst. Studying asexual propagation will shed light on how derived characters within the benthic ctenophores may have evolved.