THE FLAGELLAR APPARATUS OF CHRYSOLEPIDOMONAS DENDROLEPIDOTA (CHRYSOPHYCEAE), A SINGLE-CELLED MONAD COVED WITH ORGANIC SCALES1

The flagellar apparatus of Chrysolepidomonas dedrolepidota Peters et Andersen is similar to that of other members of the Ochromonadales, Chrysophyceae. there are four microtubular roots (R_1-4) and a system II fiber (= rhizoplast). the R₁ root consists of three microtubules that nucleate many cytoplasmic microtubules. One compressed band of 10 or more cytoplasmic microtubules is directed black along the R1 root in an anti-parallel direction. The R₂ root consists of one to two microtubules, and it extends toward the distal end of the R₁ root. The R₃ root consists of six (?seven) microtubules near its proximal end. The “a” and “f” microtubules of the R₃ root are under the short flagellum, and the “f” microtubule loops back and under the basal body, extending down to the nucleus. The R₄ root consists of one to two microtubules extending along the left side of the shot flagellum and curving under the short flagellum where it terminates near the “a” microtubule of R₃ Both flagella have a transitional plate and a transitional helix with five gyres. There is a thin, second plate in the basal body at the level of the distal end of the “c” tubules of the basal body triplets. The tripartite flagellar hairs have long lateral filaments but lack short lateral filaments. We compare the flagellar apparatus with that of other members of the Ochromonadales and members of the Hydrurales and Hibberdiales.