Txikispora | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
(unranked): | Filozoa |
Class: | Filasterea |
Family: | Txikisporidae |
Genus: | Txikispora |
Species: | T. philomaios |
Binomial name | |
Txikispora philomaios Urrutia, Feist & Bass | |
Txikispora is a genus of parasitic protists made up solely of the species Txikispora philomaios. It is the only genus in the family Txikisporidae, which is a member of the class Filasterea and is closely related to Ministeriidae. The lineage was first described in 2022 based on specimens identified from the United Kingdom. The species represents a previously undiscovered type of life that diverged extremely early from animals and fungi. [1] It parasitizes amphipods in the genera Echinogammarus and Orchestia and most frequently infects their hemolymph and hemocytes.
The Filozoan species was described in 2022 in the Journal of Eukaryotic Microbiology by Ander Urrutia, Stephen Feist, and David Bass. [2] The new generic and specific combination Txikispora philomaios means "May-loving spore", in reference to its presence in collections during only a few days during the month of May. [1] Txikispora is derived from a Basque word: txiki meaning "small" and a latin one spora meaning "spore". The specific epithet philomaios is: philo meaning "love" and maios meaning "May". [3]
A Rel homology region (RHR) was identified in Txikispora philomaios. The characteristics of the RHR of Txikispora philomaios was most similar to Tunicaraptor unikontum , suggesting a phylogenetic relationship between the two species. [4]
The species goes through several stages of life. The first is as a single spherical cell, called the monokaryotic stage. [3] It usually has a cell wall, and is characterized by a nucleus with a small nucleolus on its periphery and many small mitochondria with diverse lipoid structures. [5] The next stage is multinucleated, and consists of four cells joined together and is somewhat larger. [3] It appears to have three cells, with the fourth often hidden from view. The unicellular stage is often split off from the multicellular one. [5]
Txikispora philomaios parasitizes the amphipod genera Echinogammarus and Orchestia, but is not found in the related genera Gammarus and Melita. Individuals infected by the parasite displayed yellowing tegument, a less rigid carapace, less visible internal organs, and increased lethargy and unresponsiveness. [6] Txikispora philomaios specifically infects the hemolymph and individual hemocytes, with up to ten parasites found in a single hemocyte. Other organs that are infected are the hepatopancreas, testes, and ovaries. [7]
The Apicomplexa 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 apicoplast—with an apical complex membrane. The organelle's apical shape is an adaptation that the apicomplexan applies in penetrating a host cell.
Rusts are fungal plant pathogens of the order Pucciniales causing plant fungal diseases.
Trypanosomatida is a group of kinetoplastid unicellular organisms distinguished by having only a single flagellum. The name is derived from the Greek trypano (borer) and soma (body) because of the corkscrew-like motion of some trypanosomatid species. All members are exclusively parasitic, found primarily in insects. A few genera have life-cycles involving a secondary host, which may be a vertebrate, invertebrate or plant. These include several species that cause major diseases in humans. Some trypanosomatida are intracellular parasites, with the important exception of Trypanosoma brucei.
In biology, a biological life cycle is a series of stages of the life of an organism, that begins as a zygote, often in an egg, and concludes as an adult that reproduces, producing an offspring in the form of a new zygote which then itself goes through the same series of stages, the process repeating in a cyclic fashion.
Microsporidia are a group of spore-forming unicellular parasites. These spores contain an extrusion apparatus that has a coiled polar tube ending in an anchoring disc at the apical part of the spore. They were once considered protozoans or protists, but are now known to be fungi, or a sister group to fungi. These fungal microbes are obligate eukaryotic parasites that use a unique mechanism to infect host cells. They have recently been discovered in a 2017 Cornell study to infect Coleoptera on a large scale. So far, about 1500 of the probably more than one million species are named. 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. Approximately 10 percent of the species are parasites of vertebrates —several species, most of which are opportunistic, can infect humans, in whom they can cause microsporidiosis.
Enterocytozoon bieneusi is a species of the order Chytridiopsida which infects the intestinal epithelial cells. It is an obligate intracellular parasite.
Orchestia is a genus of amphipods in the family Talitridae. Species in Orchestia are parasitized by the Filozoan species Txikispora philomaios.
Entomophthora is a fungal genus in the family Entomophthoraceae. Species in this genus are parasitic on flies and other two-winged insects. The genus was circumscribed by German physician Johann Baptist Georg Wolfgang Fresenius (1808–1866) in 1856.
Filasterea is a proposed basal Filozoan clade of single-celled ameboid eukaryotes that includes Ministeria and Capsaspora. It is a sister clade to the Choanozoa in which the Choanoflagellatea and Animals appeared, originally proposed by Shalchian-Tabrizi et al. in 2008, based on a phylogenomic analysis with 78 genes. Filasterea was found to be the sister-group to the clade composed of Metazoa and Choanoflagellata within the Opisthokonta, a finding that has been further corroborated with additional, more taxon-rich, phylogenetic analyses.
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Marteilia is a protozoan genus of organisms that are parasites of bivalves. It causes QX disease in Sydney rock oysters and Aber disease in European flat oysters. After being infected by Marteilia, bivalves lose pigmentation in their visceral tissue, and become emaciated.
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Holomycota or Nucletmycea are a basal Opisthokont clade as sister of the Holozoa. It consists of the Cristidiscoidea and the kingdom Fungi. The position of nucleariids, unicellular free-living phagotrophic amoebae, as the earliest lineage of Holomycota suggests that animals and fungi independently acquired complex multicellularity from a common unicellular ancestor and that the osmotrophic lifestyle was originated later in the divergence of this eukaryotic lineage. Opisthosporidians is a recently proposed taxonomic group that includes aphelids, Microsporidia and Cryptomycota, three groups of endoparasites.
An amoeba, often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopods. Amoebae do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals.
Pleistophora mulleri (Pfeiffer) Georgev. 1929 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.
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Tunicaraptor is a genus of marine microbial protists containing the single species Tunicaraptor unikontum, discovered in 2020 from marine waters of Chile. It is a lineage of predatorial flagellates closely related to animals. It has a rare feeding structure not seen in other opisthokonts.
Echinogammarus is a genus of amphipod crustaceans in the family Gammaridae. The status of many of its species is incertae sedis, but its type species is Echinogammarus berilloni. Species in Echinogammarus are parasitized by the Filozoan species Txikispora philomaios.