Apicomplexa
\n| Apicomplexa |
\n |
\n |
\n| Classes & Subclasses |
\n\nClass Perkinsasida \nClass Colpodellasida \nClass Conoidasida \n    Gregarinasina \n    Coccidiasina \nClass Aconoidasida \n    Haemosporasina \n    Piroplasmasina\n |
The
Apicomplexa are a large group of almost exclusively parasitic
protozoa, characterized by a complicated apical complex at the anterior of the cell. This complex often includes an
organelle called the apicoplast, believed to be a degenerate
chloroplast. They have a pellicle composed of packed alveoli, and this and other traits indicate membership in a group called the
alveolates, among which they appear particularly closely related to the
dinoflagellates.
Two genera of free-living
flagellates,
Perkinsus and
Colpodella, are generally included here, though they may be closer to the
dinoflagellates than to the other Apicomplexa. Aside from these, all Apicomplexa are parasites, without flagella or other locomotory structures. Some important members and their associated diseases include:
The Apicomplexa include the bulk of what used to be called the Sporozoa, a group for parasitic protozoans without flagella, pseudopods, or cilia.