Haptophyte

Haptophytes
Coccolithophore (Coccolithus pelagicus)
Scientific classification
Domain:	Eukaryota
Kingdom:	Chromalveolata
Phylum:	Haptophyta Hibberd 1976
Orders
Class Pavlovophyceae    Pavlovales Class Prymnesiophyceae    Prymnesiales    Phaeocystales    Isochrysidales    Coccolithales

Haptophytes are a phylum of algae, sometimes called the Prymnesiophyta. All or most of them are single-celled photosynthetic phytoplankton.

The cells typically have two slightly unequal flagella and a unique organelle called a haptonema. This is superficially similar to a flagellum, but differs in its arrangement of microtubules, and in its use. The name comes from the Greek hapsis = touch, and nema = thread.

Classification

Molecular and morphological evidence places them in five orders; coccolithophores make up the Isochrysidales and Coccolithales. Other groups include phytoplankton which produce the toxic algal blooms.