''Atoxoplasma'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

alveolates in the

phylum In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead ...

Apicomplexa The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an ap ...

. The species in this genus infect

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s. They are spread by the orofaecal route.

History

This genus was created by Garnham in 1950. The history of this genus has been plagued with confusion. Before 1909 the species in this genus were confused with those of the genus ''

Haemoproteus ''Haemoproteus'' is a genus of alveolates that are parasitic in birds, reptiles, and amphibians. Its name is derived from Greek: ''haima'' 'blood' and ''Proteus'', a sea god that had the power to assume various shapes. The name ''Haemoproteus'' ...

''. Between 1909 and 1937 they were considered to be species of the genus ''

Toxoplasma ''Toxoplasma gondii'' () is a species of parasitic alveolate that causes toxoplasmosis. Found worldwide, ''T. gondii'' is capable of infecting virtually all warm-blooded animals, but members of the cat family (felidae) are the only known d ...

''. It was because of this historical confusion with ''Toxoplasma'' that Garnham chose the name ''Atoxoplasma'' for this genus. Garnham defined this genus to be those parasites that infect the monocytes of birds, are strictly host specific, have a granular cytoplasm and a large nucleus. His choice of type species ''Atoxoplasma avium'' was later shown to be a junior synonym of ''Atoxplasma paddae''. Lainson in 1958 published a study suggesting that these species were transmitted by ticks and that this genus was a synonym of ''

Lankesterella ''Lankesterella'' is a genus of flowering plants from the orchid family, Orchidaceae. It is found mostly in South America, with a few species extending north into Cuba, the Dominican Republic and Costa Rica. Species Species currently recognized ...

'' - a genus of species that infects frogs.Lainson R (1958) Some observations on the life-cycle of ''Atoxoplasma'', with particular reference to the parasite's schizogony and its transmission by the mite ''Dermanyssus gallinae''. Nature 182(4644):1250-1251 The genus later became regarded as a junior synonym of the genus ''

Isospora ''Isospora'' is a genus of internal parasites in the subclass Coccidia. It is responsible for the condition isosporiasis, which causes acute, non-bloody diarrhoea in immunocompromised individuals. Taxonomy At least 248 species were original ...

'' for those species that infect birds.Barta JR, Schrenzel MD, Carreno R, Rideout BA (2005) The genus ''Atoxoplasma'' (Garnham 1950) as a junior objective synonym of the genus ''Isospora'' (Schneider 1881) species infecting birds and resurrection of ''Cystoisospora'' (Frenkel 1977) as the correct genus for ''Isospora'' species infecting mammals. J Parasitol 91(3):726-727

Definition

The species in this genus develop asexually in both the

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is com ...

and intestinal cells and form

oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

s that are passed unsporulated in the feces, sporulate on the ground which then infect new hosts.Levine ND (1982) The genus ''Atoxoplasma'' (Protozoa, Apicomplexa). J Parasitol 68(4):719-723 The oocysts are tetrasporozoic, diplosporocystic and possess Stieda bodies in their sporocysts.

Life cycle

The encysted sporozoites are ingested. The sporozoites decyst and invade the intestinal wall and from there reach the liver and other tissues including the blood cells where they replicate asexually. Within the intestine they undergo sexual reproduction, undergo gametogony and fertilization. The zygotes undergo division and form cysts which are passed out with the stool.

Host records

*Canary ('' Serinus canarius'') *Israeli sparrow ('' Passer domesticus biblicus'') *Other birds of the Passeriformes order

References

{{Taxonbar, from=Q4817453 Apicomplexa genera