Stephanopogon apogon

Introduction

Stephanopogon apogon is one of two species in the genus that has been studied at both the ultrastructural and molecular phylogenetic levels. This was the first species to be described with the aid of transmission electron microscopy, and these studies demonstrated that Stephanopogon was not a member of the Ciliata (Lipscomb and Corliss 1982; Patterson and Brugerolle 1988). A culture of S. agpogon containing the euglenozoan Rhynchomonas nasuta as a food source is available at the American Type Culture Collection ATCC (50096).

The molecular phylogenetic position of this species was addressed using both actin and small subunit ribosomal RNA gene sequences; this study showed that S. apogon is closely related to the heterolobosean Percolomonas cosmopolitus (Yoon et al 2008).

Characteristics

Stephanopogon apogon has a slit-like apical cytostome, but lacks the prominent apical barbs present in other species in the genus.

• Absence of anterior barbs, truncate anterior end
• Rounded posterior end
• Cell about 50-90 µm long
• 6 longitudinal rows of flagella (cilia) on the ventral surface

References

Lipscomb, D. l. and Corliss, J. O. 1982. Stephanopogon, a phylogenetically important "ciliate," shown by ultrastructural studies to be a flagellate. Science 215:303-304.

Patterson, D. J. and Brugerolle, G. 1988. The ultrastructural identity of Stephanopogon apogon and the relatedness of the genus to other kinds of protists. Europ Europ. J. Protistol. 23:279-290.

Yoon, H. S., Grant, J., Tekle, Y. I., Wu, M., Chaon, B. C., Cole, J. C., Logsdon Jr. J. M., Patterson, D. J., Bhattacharya, D. and Katz, L. A. 2008. Broadly sampled multigene trees of eukaryotes. BMC Evol. Biol. 8:14.