title: The ultrastructural identity of Stephanopogon apogon and the relatedness of the genus to other kinds of protists.
abstract: The ultrastructural organization of the marine benthic protist Stephanopogon apogon is presented. Emphasis is placed on the structure of the mouth, the cortex, and the locomotor flagella. Viewed with a light-microscope, individuals of this species closely resemble members of the phylum Ciliophora (in terms of ciliation, body form, and presence of a discrete mouth), but Stephanopogon cells are ultrastructurally unlike all ciliophora in respect of the oral apparatus, cortical organization, and locomotor systems. The proposition that Stephanopogon is related to Euglenozoa is discussed, and is found to be supported by a single character, the form of the mitochondrial cristae. Placement of Stephanopogon in the Euglenozoa is therefore deemed to be premature.
authors.affiliation: Department of Zoology, University of Bristol, England.
authors.forename: D J
authors.initials: DJ
authors.lastname: Patterson
authors.forename: G
authors.initials: G
authors.lastname: Brugerolle