Archaea genera

Thermoplasma is a genus of archaeans. It belongs to the class Thermoplasmata, which thrive in acidic and high-temperature environments. Thermoplasma are facultative anaerobes and respire using sulfur and organic carbon. They do not contain a cell wall but instead contain a unique membrane composed mainly of a tetraether lipoglycan containing atypical archaeal tetraether lipid attached to a glucose- and mannose-containing oligosaccharide. This lipoglycan is presumably responsible for the acid and thermal stability of the Thermoplasma membrane.

Halobacterium (common abbreviation Hbt.), from Ancient Greek ἅλς (háls), meaning "salt", and "bacterium", is a genus in the family Halobacteriaceae.

Sulfolobus is a genus of microorganism in the family Sulfolobaceae. It belongs to the kingdom Thermoproteati of the Archaea domain.

Methanopyrus is a genus of methanogen, with a single described species, Methanopyrus kandleri (type strain AV19). It is a rod-shaped hyperthermophile, discovered on the wall of a black smoker from the Gulf of California at a depth of 2,000 m, at temperatures of 84–110 °C. Strain 116 was discovered in black smoker fluid of the Kairei hydrothermal field; it can survive and reproduce at 122 °C. M. kandleri also requires a high ionic concentration (>1 M) in order for growth and cellular activity. Due to the species' high resilience and extreme environment, M. kandleri is also classi

Ignicoccus is a genus of hyperthermophillic Archaea living in marine hydrothermal vents. They were discovered in samples taken at the Kolbeinsey Ridge north of Iceland, as well as at the East Pacific Rise (at 9 degrees N, 104 degrees W) in 2000.

Thermoproteus is a genus of archaeans in the family Thermoproteaceae. These prokaryotes are thermophilic sulphur-dependent organisms related to the genera Sulfolobus, Pyrodictium and Desulfurococcus. They are hydrogen-sulphur autotrophs and can grow at temperatures of up to 95 °C.

Pyrodictium is a genus in the family Pyrodictiaceae. It is a genus of submarine hyperthermophilic Archaea whose optimal growth temperature range is 80 to 110°C. They have a unique cell structure involving a network of cannulae and flat, disk-shaped cells. Pyrodictium are found in the porous walls of deep-sea vents where the temperatures inside get as high as 400°C, while the outside marine environment is typically 3°C. Pyrodictium is apparently able to adapt morphologically to this type of hot–cold habitat.

Haloquadratum (common abbreviation: Hqr.) is a genus of archaean, belonging to the family Haloferacaceae. The first species to be identified in this group, Haloquadratum walsbyi, is unusual in that its cells are shaped like square, flat boxes.

Methanosarcina is a genus of euryarchaeote archaea that produce methane. These single-celled organisms are known as anaerobic methanogens that produce methane using all three metabolic pathways for methanogenesis. They live in diverse environments where they can remain safe from the effects of oxygen, whether on the earth's surface, in groundwater, in deep sea vents, and in animal digestive tracts. Methanosarcina grow in colonies.

Thermococcus is a genus of thermophilic Archaea in the family the Thermococcaceae.

Archaeoglobus is a genus of archaeans in the phylum Euryarchaeota. Archaeoglobus can be found in high-temperature oil fields where they may contribute to oil field souring.

Ferroplasma is a genus of Archaea that belong to the family Ferroplasmaceae. Members of the Ferroplasma are typically acidophilic, pleomorphic, irregularly shaped cocci.

Pyrococcus is a genus of Thermococcaceaen archaeans.

Pyrolobus is a genus of archaeans in the family Pyrodictiaceae.

thumb|Schematic map of the pPO1 plasmid from the hyperacidophile Picrophilus oshimae

Pyrobaculum is a genus of archaeans in the family Thermoproteaceae.

Haloarcula (common abbreviation Har.) is a genus of extreme halophilic Archaea in the class of Halobacteria.

Ferroglobus is a genus of the Archaeoglobaceae.

Methanococcus is a genus of coccoid methanogens of the family Methanococcaceae. They are all mesophiles, except the thermophilic M. thermolithotrophicus and the hyperthermophilic M. jannaschii. The latter was discovered at the base of a "white smoker" chimney at 21°N on the East Pacific Rise and it was the first archaeal genome to be completely sequenced, revealing many novel and eukaryote-like elements.

Methanobacterium (from Latin methanum, meaning "methane", and bactērium) is a genus of the Methanobacteria class in the Archaea domain, which produce methane as a metabolic byproduct. Despite the name, this genus belongs not to the bacterial domain but the archaeal domain (for instance, they lack peptidoglycan in their cell walls). Methanobacterium are nonmotile and live without oxygen, which is toxic to them, and they only inhabit anoxic environments.

Methanobrevibacter is a genus of archaeans in the family Methanobacteriaceae. The species within Methanobrevibacter are strictly anaerobic archaea that produce methane, for the most part through the reduction of carbon dioxide via hydrogen. Most species live in the intestines of larger organisms, such as termites and are responsible for the large quantities of greenhouse gases that they produce.

Methanocella is a genus of archaeans in the phylum Methanobacteriota.

Methanomicrobium is a genus of archaeans in the family Methanomicrobiaceae. The cells are shaped like short bars and do not form endospores. They produce methane via the reduction of carbon dioxide with hydrogen or formate. They cannot metabolize acetate, methylamines, or methanol.

Acidianus is a genus of archaeans in the family Sulfolobaceae.

Methanoculleus is a genus of microbes within the family Methanomicrobiaceae. The species of the genus Methanoculleus live in marine environments brackish water, and are very common in bioreactors, landfills, and wastewater. Unlike other archaea, Methanoculleus and some species of related genera can use ethanol and some secondary alcohols as electron donors as they produce methane. This has implications as the production of methane as a greenhouse gas and consequences with respect to global climate change.

Haloferax (common abbreviation: Hfx.) is a genus of halobacteria in the order Haloferacaceae.

Halococcus (common abbreviation: Hcc.), from Ancient Greek ἅλς (háls), meaning "salt", and κόκκος (kókkos), meaning "berry", is a genus of archaeans in the family Halococcaceae.

Thermofilum is a genus of archaea in the family Thermofilaceae.

Methanothermus is a genus of microbes within the family Methanothermaceae. The species within this genes are hyperthermophiles and strictly anaerobic. They produce energy through the reduction of carbon dioxide with hydrogen to produce methane. it is found in hydrothermal vents with temperatures as high as 85 °C and pH 6.5.

Halorubrum is a genus in the family Halorubraceae. Halorubrum species are usually halophilic and can be found in waters with high salt concentration such as the Dead Sea or Lake Zabuye.

Sulfurisphaera is a genus of the Sulfolobaceae.

Geoglobus is a hyperthermophilic member of the Archaeoglobaceae within the Euryarchaeota. It consists of two species, the first, G. ahangari, isolated from the Guaymas Basin hydrothermal system located deep within the Gulf of California. As a hyperthermophile, it grows best at a temperature of 88 °C and cannot grow at temperatures below 65 °C or above 90 °C. It possess an S-layer cell wall and a single flagellum. G. ahangari is an anaerobe, using poorly soluble ferric iron (Fe3+) as a terminal electron acceptor. It can grow either autotrophically using hydrogen gas (H2) or heter

Methanocorpusculum is a genus of Archaea within the family Methanocorpusculaceae. The species within Methanocorpusculum were first isolated from biodisgester wastewater and activated sludge from anaerobic digestors. In nature, they live in freshwater environments. Unlike most other methanogenic archaea, they do not require high temperatures or extreme salt concentrations to live and grow.

Methanosphaera is a genus of Archaea within the family Methanobacteriaceae. It was distinguished from other genera within Methanobacteriaceae in 1985 on the basis of the oligonucleotide sequence of its 16S RNA. Like other archaea within Methanobacteriaceae, those of Methanosphaera are methanogens, but while most use formate to reduce carbon dioxide, those of Methanosphaera use hydrogen to reduce methanol to methane.

Methanolobus is a genus of methanogenic archaea within the family Methanosarcinaceae. These organisms are strictly anaerobes and live exclusively through the production of methane, but the species within Methanolobus cannot use carbon dioxide with hydrogen, acetate or formate, only methyl compounds. The cells are irregular coccoid in form and approximately 1 μm in diameter. They do not form endospores. They are Gram negative and only some are motile, via a single flagellum. They are found in lake and ocean sediments that lack oxygen.

Methanocaldococcus formerly known as Methanococcus is a genus of coccoid methanogen archaea. They are all thermophiles, including M. infernus and the hyperthermophilic M. jannaschii. The latter was discovered at the base of a “white smoker” chimney at 21°N on the East Pacific Rise and it was the first archaean genome to be completely sequenced, revealing many novel and eukaryote-like elements.

Methanosaeta is a genus of archaeans in the family Methanosaetaceae. Like other species in this family, those of Methanosaeta metabolize acetate as their sole source of energy. The genus contains two species, Methanosaeta concilii, which is the type species (type strain GP6) and Methanosaeta thermophila. For a time, some scientists believed there to be a third species, Methanosaeta soehngenii, but because it has not been described from a pure culture, it is now called Methanothrix soehngenii.

Aeropyrum is a genus of archaea in the family Desulfurococcaceae.

Methanolacinia is a genus of archaeans in the family Methanomicrobiaceae. The cells are bar-shaped and irregular 0.6 μm in diameter and 1.5–2.5 μm in length. They do not form endospores. Most are non-motile, but some have a single flagellum. They are strictly anaerobic. They produce methane through the reduction of carbon dioxide with hydrogen and cannot use formate, acetate or methyl compounds as substrates.

Methanogenium is a genus of archaeans in the family Methanomicrobiaceae. The type species is Methanogenium cariaci.

Methanospirillum is a genus of microbes within the family Methanospirillaceae. All its species are methanogenic archaea. The cells are bar-shaped and form filaments. Most produce energy via the reduction of carbon dioxide with hydrogen, but some species can also use formate as a substrate. They are Gram-negative and move using archaella on the sides of the cells. They are strictly anaerobic, and they are found in wetland soil and anaerobic water treatment systems.

Vulcanisaeta is a genus of archaeans in the family Thermoproteaceae.

Methanococcoides is a genus of archaeans in the family Methanosarcinaceae.

Methanohalobium is a genus of archaeans in the family Methanosarcinaceae. Its genome has been sequenced. The genus contains one species, M. evestigatum.

Methanoregula is a genus of archaeans in the order Methanomicrobiales. It was isolated from an acidic peat bog. It produces methane at the lowest pH of any known organism.

Staphylothermus is a genus of archaeans in the family Desulfurococcaceae.

Metallosphaera is a genus of archaeans in the family Sulfolobaceae.

Methanoplanus is a genus of archaeans in the family Methanomicrobiaceae, comprising three species of methanogenic, or methane-producing, archaea. The cells are irregular coccoid in shape, tend to stain Gram-negative and do not form endospores.

thumb|upright=1.0| Phase contrast image of Methano­thermobacter marburgensis DSM 2133. Specimen was obtained in late exponential phase from a fed-batch fermentation. The cells are rod shaped and elongated.

Methanofollis is a genus of archaean in the family Methanomicrobiaceae.

Methanohalophilus is a genus of archaeans in the family Methanosarcinaceae.

Desulfurococcus is a genus of archaeans in the family Desulfurococcaceae.

Caldisphaera is a genus of archaea in the family Caldisphaeraceae.

Cenarchaeum is a monotypic genus of archaeans in the family Nitrosopumilaceae. The marine archaean Cenarchaeum symbiosum is psychrophilic and is found inhabiting marine sponges. Cenarchaeum symbiosum was initially detected as a major symbiotic microorganism living within (it is an endosymbiont of) the sponge Axinella mexicana. It has been ubiquitously detected in the world oceans at lower abundances, while in some genera of marine sponges it is one of the most abundant microbiome members. Its genome sequence and diversity has been investigated in detail finding unique metabolic products and it

Methanothermococcus is a genus of archaeans in the family Methanococcaceae. The cells are shaped like irregular bars and tend to be Gram-negative. They are mobile via polar flagella. They require acetate to grow.

Stygiolobus is a genus in the family Sulfolobaceae.

Methanocalculus is a genus of archaeans in the order Methanomicrobiales, and is known to include methanogens.

Acidiplasma is a genus in the phylum Euryarchaeota (Archaea).

Thermocladium is a genus of archaeans in the family Thermoproteaceae.

Methanomethylovorans is a genus of microorganisms in the family Methanosarcinaceae. This genus was first described in 1999. The species within it generally live in freshwater environments, including rice paddies, freshwater sediments and contaminated soil. They produce methane from methanol, methylamines, dimethyl sulfide and methanethiol. With the exception of M. thermophila, which has an optimal growth temperature of 50 °C, these species are mesophiles and do not tend to grow at temperatures above 40 °C.