Taxobox name Ascetosporea domain Eukaryota regnum Rhizaria phylum Cercozoa classis Ascetosporea classis authority Sprague, 1979 subdivision ranks Genera subdivision Haplosporidiidae Haplosporidium 23 species Minchina 5 species Urosporidium 8 species Paramyxidae Marteilia Paramartelia Paramyxa The Ascetosporea are a group of protist s that are parasite s of animals, especially marine invertebrate s. There are two groups, the haplosporids and paramyxids, which are not particularly similar morphologically but consistently group together on molecular trees, which place them near the base of the Cercozoa . ref cite journal author Thomas Cavalier Smith & Ema E. Y. Chao year 2003 title Phylogeny of Choanozoa, Apusozoa, and other Protozoa and early eukaryote megaevolution journal Journal of Molecular Evolution volume 56 issue 5 pages 540 563 pmid 12698292 doi 10.1007 s00239 002 2424 z ref Both produce spore s without the complex structures found in similar groups such as polar filaments or tubules . Haplosporid spores have a single cell nucleus nucleus and an opening at one end, covered with an internal diaphragm or a distinctive hinged lid. After emerging, it develops within the cells of its host, usually a marine Mollusca mollusc or annelid , although some infect other groups or freshwater species. The trophic cell is generally multinucleate . Paramyxids develop within the digestive system of marine invertebrates, and undergo internal budding to produce multicellular spores. A 2009 study concluded that Haplosporidium species form a paraphyletic group and that the taxonomy of the haplosporidians needs a thorough revision. ref cite journal author P. M. Hine, R. B. Carnegie, E. M. Burreson & M. Y. Engelsma year 2009 title Inter relationships of haplosporidians deduced from ultrastructural studies journal Diseases of Aquatic Organisms volume 83 issue 3 pages 247 256 doi 10.3354 ... Parasites protist stub parasite stub cs Haplosporidie de Haplosporidia es Ascetosporea ja ... more details
Taxobox regnum Rhizaria phylum Cercozoa subphylum Endomyxa subphylum authority Tom Cavalier Smith Cavalier Smith , 2002 subdivision ranks Classes subdivision Proteomyxidea Phytomyxea Gromiidea Ascetosporea Endomyxa is a subphylum of Rhizaria . ref name urlCercozoa cite web url http tolweb.org Cercozoa title Cercozoa format publisher Tree of Life Web Project accessdate 2009 05 21 ref ref name pmid18952499 cite journal author David Bass, Ema E. Y. Chao, Sergey Nikolaev, Akinori Yabuki, Ken ichiro Ishida, C dric Berney, Ursula Pakzad, Claudia Wylezich and Thomas Cavalier Smith title Phylogeny of novel naked filose and reticulose Cercozoa Granofilosea cl. n. and Proteomyxidea revised journal Protist journal Protist volume 160 issue 1 pages 75 109 year 2009 month February pmid 18952499 doi 10.1016 j.protis.2008.07.002 url http linkinghub.elsevier.com retrieve pii S1434 4610 08 00044 8 ref References Reflist Rhizaria Category Rhizaria protist stub ... more details
italictitle Taxobox name Bonamia ostreae domain Eukaryota regnum Rhizaria phylum Cercozoa classis Ascetosporea familia Haplosporidiidae genus Bonamia species B. ostreae binomial Bonamia ostreae binomial authority Bonamia ostreae is a parasitic protist in the phylum Haplosporidia that can cause lethal infections in shellfish, particularly the European flat oyster, Ostrea edulis . Infection in oysters rarely results in clinical signs of disease and often the only indication of the infection is increased mortality. ref name FHI http www.scotland.gov.uk Topics marine Fish Shellfish 18610 diseases notifiableDisease Bonamiaostreae Scottish Fish Health Inspectorate ref The Australian flat oyster, Ostrea angasi , has also been infected with Bonamia parasites. ref http www.fish.wa.gov.au docs pub FHSlideofQuarter 200603.php?0408 Department of Fisheries, Western Australia. ref Pathology The cells of Bonamia ostreae measure 2 3 m in diameter and are found within the Hemocyte haemocytes of the oyster. Lesions occur with focal infiltration of the haemocytes within the connective tissue of the mantle and gills, and in the vascular sinuses near the digestive gland, intestine and stomach. Infection seems to be correlated to haemocyte destruction and diapedesis . ref name FHI Epidemiology A study in the Netherlands of the epidemiology of European flat oysters, Ostrea edulis , infected with Bonamia ostreae showed that the parasite was present throughout the year and was detected in all oyster weight classes. The study analyzed the prevalence relative to O. edulis density, biomass and a range of environmental parameters. Prevalence was greatest in the largest oysters and was higher in spring than in the autumn, perhaps because of the mortality of these shellfish during the summer. Mortality seemed to be correlated with higher water temperatures and oysters seemed to be more susceptible to infection after seasons with lower food availability or lower salinity levels. ref cite journal doi ... more details
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