THE ARCHITECTURE OF THE FLAGELLAR APPARATUS OF PRYMNESIUM-PATELLIFERA (PRYMNESIOPHYTA)

The flagellar apparatus of the small prymnesiophyte Prymnesium patellifera has been analysed and a reconstruction is presented. Externally, the cell carries two sub-equal flagella and a short non-coiling haptonema. Within the cell, there are four microtubular roots and a number of fibrous bands, the latter interconnecting the two basal bodies and the haptonema base. One of the roots (r1) consists of a sheet of up to 25 microtubules originating close to the proximal extremity of the haptonema base, but the other three roots are composed of between 1 and 4 microtubules only. Distally, a large striated fibrous auxiliary connecting root extends across the anterior part of the cell linking root r1 and a mitochondrial profile on the opposite side of the cell. The arrangement of the components of the flagellar apparatus of P. patellifera is commensurate with the general pattern found in many prymnesiophytes other than members of the Pavlovales, but there are a number of differences in detail from the other species described hitherto. © 1990 The Botanical Society of Japan.