Ultrastructural observations on some marine choanoflagellates from the coast of denmark

Abstract

The external morphology of eight species of choanoflagellates representing seven genera has been investigated with the electron microscope. Descriptions of three new species (Pleura- siga cupula, Diaphanoeca pedicellata Stephanoeca pedicellata), a new variety (Pleurasiga minima var. minuta) an emended description of Salpingoeca natans Grontved are provided. All species possess a characteristic protoplast with a single anterior flagellum surrounded by a collar of tentacles all possess a lorica composed of costae. In two species (Acanthoeca brevipoda Ellis Diplotheca costata Valkanov) the costal strips forming the posterior chamber are broader than usual. Sections of two species show the presence of a very thin delicate membrane which secures the protoplast to the lorica. © 1972 Taylor & Francis Group, LLC.