Octactis

Octactis
Illustration of Octactis speculum silica skeletons by Stöhr (1880)
Scientific classification
Domain: Eukaryota
Clade: Diaphoretickes
Clade: Sar
Clade: Stramenopiles
Phylum: Ochrophyta
Class: Dictyochophyceae
Order: Dictyochales
Family: Dictyochaceae
Genus: Octactis
Schiller, 1925 emend. F.H.Chang, J.M.Grieve & J.E.Sutherland, 2017
Species
  • O. octonaria
  • O. speculum

Octactis is a genus of silicoflagellates, marine photosynthetic unicellular protists that take the form of either flagellates or axopodial amoebae. Described by Josef Schiller in 1925, Octactis contains various species of marine phytoplankton, some of them responsible for algal blooms that are toxic to fish.