The Apicomplexa are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of plastid called an apicoplast, and an apical complex structure. The organelle is an adaptation that the apicomplexan applies in penetration of a host cell.
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 vertebrate host during a blood meal. Parasites grow within a vertebrate body tissue before entering the bloodstream to infect red blood cells. The ensuing destruction of host red blood cells can result in disease, called malaria. During this infection, some parasites are picked up by a blood-feeding insect, continuing the life cycle.
Nosema apis is a microsporidian, a small, unicellular parasite recently reclassified as a fungus that mainly affects honey bees. It causes nosemosis, also called nosema, which is the most common and widespread disease of adult honey bee diseases. The dormant stage of N. apis is a long-lived spore which is resistant to temperature extremes and dehydration, and cannot be killed by freezing the contaminated comb. Nosemosis is a listed disease with the Office International des Epizooties (OIE).
Microsporidia are a group of spore-forming unicellular parasites. They were once considered protozoans or protists, but are now known to be fungi, or a sister group to fungi. Loosely 1500 of the probably more than one million species are named now. Microsporidia are restricted to animal hosts, and all major groups of animals host microsporidia. Most infect insects, but they are also responsible for common diseases of crustaceans and fish. The named species of microsporidia usually infect one host species or a group of closely related taxa. Several species, most of which are opportunistic, also infect humans.
Microsporidiosis is an opportunistic intestinal infection that causes diarrhea and wasting in immunocompromised individuals. It results from different species of microsporidia, a group of microbial (unicellular) fungi.
Nosema is a genus of microsporidian parasites. The genus, circumscribed by Swiss botanist Karl Wilhelm von Nägeli in 1857, contains 81 species. Most parasitise insects and other arthropods, and the best-known Nosema species parasitise honeybees, where they are considered a significant disease by beekeepers, often causing a colony to fail to thrive in the spring as they come out of their overwintering period. Eight species parasitize digeneans, a group of parasitic flatworms, and thus are hyperparasites, i.e., parasites of a parasite.
A xenoma is a growth caused by various protists and fungi, most notably microsporidia. It can occur on numerous organisms; however is predominantly found on fish.
Loma is a genus of microsporidian parasites, infecting fish. The taxonomic position of Loma in the family Glugeidae has been questioned by DNA sequencing results.
Encephalitozoon intestinalis is a parasite. It can cause microsporidiosis.
Fibrillanosema crangonycis is a species of fungus in the phylum Microsporidia. This species is morphologically identical to uncharacterized microsporidia from populations of North American amphipods. It is, however, distinct from microsporidia found in European populations of amphipods.
Dikerogammarus villosus, also known as the killer shrimp, is a species of amphipod crustacean native to the Ponto-Caspian region of eastern Europe, but which has become invasive across the western part of the continent. In the areas it has invaded, it lives in a wide range of habitats and will kill many other animals, often not eating them. It is fast-growing, reaching sexual maturity in 4–8 weeks. As it has moved through Europe it threatens other species and has already displaced native amphipods as well as other amphipods which had invaded areas previously.
Nosema bombi is a microsporidian, a small, unicellular parasite recently reclassified as a fungus that mainly affects bumble bees. The parasite infects numerous Bombus spp. at variable rates, and has been found to have a range of deleterious effects on its hosts.
Dikerogammarus haemobaphes is a species of freshwater gammarid crustacean. These gammarids are commonly known as demon shrimp, likely because they are an extremely successful invasive species. Native to the Ponto Caspian basin, Dikerogammarus haemobaphes expanded their range in 1955. This expansion began in Lake Balaton, Hungary and then spread into certain rivers and lakes in Austria, Belgium, Germany, Poland, Russia, Ukraine, and the United Kingdom. These crustaceans likely broadened their range due to the interconnection of waterways in Europe and the use of transportation vectors such as boats and ships.
Loma salmonae is a species of microsporidian parasite, infecting Pacific salmon. L. salmonae is the causative agent of microsporidial gill disease of salmon. It is an intracellular parasite which induces respiratory distress, secondary infection, and increased mortality rates.
Pleistophora mulleri is a parasite of the amphipod Gammarus duebeni celticus. The parasite targets the freshwater shrimp species and has shown higher rates of cannibalism, which in turn, affects biological communities and ecology.
Ordospora colligata is an intracellular parasite belonging to the Microsporidia. It is an obligatory gut parasite with the crustacean Daphnia magna as its only host. So far it has been reported from Europe and Asia.
Hamiltosporidium is a genus of Microsporidia, which are intracellular and unicellular parasites. The genus, proposed by Haag et al. in 2010, contains two species; Hamiltosporidium tvaerminnensis, and Hamiltosporidium magnivora. Both species infect only the crustacean Daphnia magna (Waterflea).
Nematocida parisii, the nematode-killer from Paris, is a species of Microsporidia fungi. It is found in wild isolates of Caenorhabditis elegans. The species replicates in the intestines of C. elegans.
Enterospora nucleophila is a microsporidian infecting the gilt-head bream. It develops primarily within the nuclei of rodlet cells and enterocytes, at the intestinal epithelium. It can also be found in cytoplasmic position within other cell types, including phagocytes, at subepithelial layers. It is the causative agent of emaciative microsporidiosis of gilthead sea bream, a chronic condition manifested as a severe growth arrestment, normally accompanied by trickling mortality.
