Ultrastructural Analysis Of The Aseptate Gregarine Pterospora, A Parasite of The Bamboo Worm Axiothella Mucosa.

Abstract

The gregarine Pterospora is a parasite found in the body cavities of bamboo worms (Polychaeta: Maldanidae). The gamont stage of Pterospora has a bizarre structure with a main cell body and multiple posterior cytoplasmic extensions (Fig. 1). The cells are found in pairs within the coelom of the host and move by cytoplasmic streaming as they fill and empty their posterior extensions. Reports of this parasite in the literature are few (see references 1 & 2 for a review) and no ultrastructural details have been published regarding the genus. This study examines the fine structure of the gamont stage with particular emphasis on the structure of the pellicle.The maldanid worm Axiothella mucosa was collected by shovel in St. Andrew Bay, Florida and returned to the Troy State University campus. Pterospora spp. gamonts were pipetted from minced setigers of the worms and fixed in 3% glutaraldehyde buffered with 0.05M sodium cacodylate, pH 7.5, for 1-6 hours.