BOT4404 Main Page

FIU Home

FIU Marine Biology Home

Dept. Biology Home

Frank Jochem Home


Introduction to the Ochrophytes
  • Ochrophytes: Group of algal division that appear brown/golden instead of green (ochro = brown); also referred to as Chromophytes
  • Flagella ultrastructure changed former grouping of chromophytes to the new ochrophytes; all cells exhibit heterokont flagella = two different flagella; new systematics confirmed by genetic information, including relationship of some heterotrophic organisms (protozoa, oomycetes)
  • Flagella: one long, forward flagellum with two rows of stiff, three-parted hairs (mastigoneme); one short, smooth flagellum with basal granule (light sensing)
  • Flagellar root: origin of flagella perpendicular, each bearing two microtubular roots (R1 R4); R3 is looplike, associated with phagotrophy
  • Loss of R3 is associated with loss of phagotrophy in synurophyceans
  • Diversification of flagellar apparatus in various groups of ochrophytes, particularly of R3 loop
  • Sequencing of SSU rDNA indicate that ochro- phytes are monophyletic
  • Diatoms are phylogenetically more separated from other groups of ochrophytes