''Plasmodium vaughani'' is a parasite of the genus ''

Plasmodium ''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a blood-feeding insect host which then injects parasites into a vert ...

'', and the type species of the subgenus ''

Novyella ''Novyella'' is a subgenus of the genus ''Plasmodium'' - all of which are parasites. The subgenus was created in 1963 by Corradetti ''et al.'' Species in this subgenus infect birds. It unites the avian malaria parasites with small erythrocytic m ...

''. As in all ''Plasmodium'' species, ''P. vaughani'' has both

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

and

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...

hosts. The vertebrate hosts for this parasite are

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

Taxonomy

The parasite was first described by Novy & MacNeal in 1904.

Subspecies

*'' Plasmodium vaughani merulae'' Corradetti and Scanga 1972 *'' Plasmodium vaughani tenue'' Laveran and Marullaz 1914 *'' Plasmodium vaughani vaughani'' Novy and MacNeal 1904

Description

The length of the asexual cycle is 24 hours. Trophozoites: Ring forms are unusual. The trophozoite is usually irregular in outline. The nucleus is small and there may be a single clear outgrowth of the cytoplasm. One or two small pigment granules may be seen. These forms are found in mature and polychromatic erythrocytes. Schizonts: These are usually found in a polar or sub polar position within the host cell but may be found anywhere within the cell. They are found in mature or polychromatic erythrocytes. Mature forms measure 2.3 to 5.4 micrometres in width and 1.5 to 4.4 micrometres in length. They are irregular in shape but tend to be round or ovoid. Within each schizont are 4-8

merozoites 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 is ...

. These are usually arranged in a fan like fashion but may occur at random. A transparent globule may be present along with one to three pigment granules. The host nucleus is not normally displaced.

Gametocytes A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametids during gametogenesis. Male gametocytes are called ''spermatocytes'', and female gametocytes are called ''oocytes''. Development ...

: The macro- and microgametocytes are very similar except for size in this species. They are elongated, possess 2-24 (usually 10) pigment granules which may be found in clumps and are usually found in mature erythrocytes. The nucleus is pale, compact and central in position. The gametocyte usually lies along the host cell nucleus but young gametoctyes may adhere to the host cell membrane. The host nucleus is not normally displaced. They are 8.0 to 13.7 micrometres in length and 1.2 to 2.8 micrometres in width. Asexual replication appears to occur in three ways: (1) by repeated binary fission of the chromatin with eventual splitting of the cytoplasm (2) by the splitting of an elongate parasite into merozoites having a bead-like arrangement (3) by the similar breaking-up of a ring-shaped form with a resulting ring of merozoites

Distribution

''P. vaughani'' has been reported from regions across the globe, with the exception of Australia. . .

Hosts

The type host of ''P. vaughani'' is ''

Turdus migratorius The American robin (''Turdus migratorius'') is a migratory bird of the true thrush genus and Turdidae, the wider thrush family. It is named after the European robin because of its reddish-orange breast, though the two species are not closely ...

''. However, various other birds can be infected by ''P. vaughani'', including the canary which has been used as an experimental host in studies. Different strains of ''P. vaughani'' develop in different mosquitoes. Most ''P. vaughani'' do not develop in most '' Aedes'', '' Anopheles'', or '' Culex'' mosquitoes; however, specific strains of ''P. vaughani'' have been described that replicate in '' Culiseta morsitans'' and '' Culex pipiens''. Additional known hosts for this species include the warbler (''

Acrocephalus schoenobaenus The sedge warbler (''Acrocephalus schoenobaenus'') is an Old World warbler in the genus '' Acrocephalus''. It is a medium-sized warbler with a brown, streaked back and wings and a distinct pale supercilium. Sedge warblers are migratory, crossing ...

''), the blackbird ('' Agelaius phoeniceus''), the goldfinch ('' Carduelis carduelis''), the blue jay (''

Cyanocitta cristata The blue jay (''Cyanocitta cristata'') is a passerine bird in the family (biology), family Corvidae, native to eastern North America. It lives in most of the eastern and central United States; some eastern populations may be migratory. Resident ...

''), the yellow warbler ('' Setophaga petechia''), the robin ('' Erithacus rubecula''), junco ('' Junco hyemalis hyemalis''), the red-billed leiothrix ('' Leiothrix lutea''), the bullfinch ('' Loxigilla violacea''), house sparrow ('' Passer domesticus''), the weaver (''

Ploceus cucullatus The village weaver (''Ploceus cucullatus''), also known as the spotted-backed weaver or black-headed weaver (the latter leading to easy confusion with '' P. melanocephalus''), is a species of bird in the family Ploceidae found in much of sub-Sa ...

''), the grackle ('' Quiscalus quiscula''), the canary ('' Serinus canaria''), the blackcap ('' Sylvia atricapilla''), the pigeon (''

Spilopelia senegalensis The laughing dove (''Spilopelia senegalensis'') is a small pigeon that is a resident breeder in Africa, the Middle East, South Asia, and Western Australia where it has established itself in the wild after being released from Perth Zoo in 1898. Th ...

''), eastern meadowlark ('' Sturnella magna''), starling ('' Sturnus vulgaris'') black-faced grassquit (''

Tiaris bicolor The black-faced grassquit (''Melanospiza bicolor'') is a small bird. It is recognized as a tanager closely related to Darwin's finches. It breeds in the West Indies except Cuba, on Tobago but not Trinidad, and along the northern coasts of Colomb ...

''), white-eyed thrush ('' Turdus jamaicensis''), the blackbird (''

Turdus merula The common blackbird (''Turdus merula'') is a species of true thrush. It is also called the Eurasian blackbird (especially in North America, to distinguish it from the unrelated New World blackbirds), or simply the blackbird where this does not ...

'') and American sparrows ('' Zonotrichia'' species).

Role in disease

Naturally and experimentally infected birds do not appear to show signs of illness from infection with ''P. vaughani''.

References

{{DEFAULTSORT:Plasmodium Vaughani vaughani Parasites of birds