Meeting Abstract

82.5  Sunday, Jan. 6  Biomechanics of the Pharyngeal Musculature in Stenostomum virginianum (Catenulida) SMITH III, Julian P.S.*; DAVIS III, Harold; Dept of Biology, Winthrop University smithj@winthrop.edu

In culture, Stenostumum virginianum feeds readily on Paramecium spp., which it captures by rapidly flaring the pharyngeal lumen, sucking in the prey, as originally described by Nuttycombe. High-speed videomicroscopy reveals that a pharyngeal flare is preceeded by a constriction of the body-wall musculature just posterior to the pharynx, which isolates the pseudocoel in the head region from that of the trunk, allowing rapid dilation of the pharyngeal lumen by radial muscles. Confocal microscopy of Alexa488/phalloidin-labeled specimens reveals muscles associated with the pharynx that are likely to be involved in stepwise production of a pharyngeal flare, prey-capture, and subsequent transfer of the prey to the gut.