Conoidasida

Conoidasida
Eimeria maxima oocysts
Scientific classification
Domain:	Eukaryota
Kingdom:	Chromalveolata
Superphylum:	Alveolata
Phylum:	Apicomplexa
Class:	Conoidasida
Orders
Eucoccidiorida

Conoidasida is a class of protists.

The class was defined in 1988 by Levine and contains two subclasses - the coccidia and the gregarines. All members of this class have a complete, hollow, truncated conoid. Gregarines tend to parasitize invertebrates with the mature gamonts being extracellular, the coccidia mostly infect vertebrates and have intracellular gamonts.

Description

A conoid is found in most species and when present forms complete but truncated cone.

Sexual and asexual reproduction are present in lifecycle of all species. Each zygote normally forms an oocyst wall within which it undergoes meiosis. This is sometimes followed by mitosis. This process of sporogony produces mobile vermiform sporozoites.

Mitotic divisions also occur during merogony of the feeding stages (trophozoites) and during gametogony.

Microgametes of some species are flagellated

Locomotion of other gametes and any other mobile stages is by gliding or body flexion.

Some species possess pseudopodia but use them only in phagocytosis.

External links

• "Conoidasida". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=553100. Retrieved June 1, 2007.