Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

is one of the most physically and chemically extreme terrestrial environments to be inhabited by lifeforms. The largest plants are mosses, and the largest animals that do not leave the continent are a few species of insects. Antarctic microbiome

Climate and habitat

Although most of the continent is covered by glacial ice sheets, ice-free areas comprising approximately 0.4% of the continental land mass are discontinuously distributed around the coastal margins. The McMurdo Dry Valleys region of

is a

polar desert Polar deserts are the regions of Earth that fall under an ice cap climate (''EF'' under the Köppen classification). Despite rainfall totals low enough to normally classify as a desert, polar deserts are distinguished from true deserts (' or ' un ...

characterized by extremely low annual precipitation and an absence of

vascular plant Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They al ...

s and

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, ...

s; microbial activity dominates biological functioning. Mean summer high and winter low temperatures in the dry valleys are Because precipitation is both infrequent and low, seasonal water availability in hydrologically connected soils make areas adjacent to water bodies more hospitable relative to dry upland soils. Polar ecosystems are particularly sensitive to

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

, where small changes in temperature result in greater changes in local

hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...

, dramatically affecting

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...

processes.

Soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

s in

are nearly two-dimensional habitats, with most biological activity limited to the top four or five inches by the permanently frozen ground below.Baskin, Yvonne. ''Under Ground: How Creatures of Mud and Dirt Shape Our World.'' Washington, DC: Island Press, 2005. 14-37. Environments can be limiting due to soil properties such as unfavorable mineralogy, texture,

structure A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ...

, salts, pH, or moisture relationships.Cameron, R.E. "Cold desert characteristics and problems relevant to other arid lands." ''Arid Lands In Perspective'' (1969): 169-205. Visible sources of

organic matter Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have c ...

are absent for most of continental Antarctica.

Dry Valley A dry valley may develop on many kinds of permeable rock, such as limestone and chalk, or sandy terrains that do not regularly sustain surface water flow. Such valleys do not hold surface water because it sinks into the permeable bedrock. There ...

soil ecosystems are characterized by large variations in temperature and light regimes, steep chemical gradients and a high incidence of

solar radiation Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Solar irradiance is measured in watts per square metre (W/m ...

with an elevated ultraviolet B (UVB) light component. Dry Valley soils originate from weathering of

bedrock In geology, bedrock is solid Rock (geology), rock that lies under loose material (regolith) within the crust (geology), crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface mater ...

and glacial tills that consist of

granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

s and

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causin ...

s. Space within these rocks provide protection for microorganisms against some (but not all) of these conditions: i.e., protection from wind scouring and surface mobility, a reduction in UV exposure, reduced

desiccation Desiccation () is the state of extreme dryness, or the process of extreme drying. A desiccant is a hygroscopic (attracts and holds water) substance that induces or sustains such a state in its local vicinity in a moderately sealed container. ...

and enhanced water availability, and thermal buffering. Half of the soils in the Dry Valleys have subsurface ice, either as buried massive ice or as ice-cemented soil (

permafrost Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface ...

). The permafrost layer is typically within of the soil surface.

Microorganisms overview

The harsh environment and low availability of

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

and water support a simplified community of

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

es,

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

and red, orange, and black

cyanobacteria Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blu ...

near lakes and ephemeral streams. Living among the mats are

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

s, molds, and an array of microscopic

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s that feed on microbes,

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

, and

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

protozoa Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...

rotifer The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John H ...

tardigrade Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär ...

s, and occasionally,

mite Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear evid ...

s and

springtail Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects (the other two are the Protura and Diplura). Although the three orders are sometimes grouped together in a class called Ento ...

s. Even simpler communities exist in the

arid A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...

soils that occupy the majority of the landscape. Microbes in

adapt to aridity the same way microbes in hot deserts do: when water becomes scarce, the organisms simply dry up, shut down

metabolic activity Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...

, and wait in a cryptobiotic state until water again becomes available. Microbes can also go dormant in a cryptobiotic state known as anhydrobiosis when they become dehydrated due to low water availability. A more extreme survival method would be long term natural cryopreservation. Samples of

sediments aged 5–10 thousand to 2-3 million years old have been found to contain viable micromycete and bacterial cells.

Algae

Algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

is present in almost all ice-free areas and occurs in

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

s, as

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s on

es, in

l mats and in

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

of lakes and ponds. It is also possible to find algae associated with rocks or living in the thin film of melted water in the snow patches. Presently there are over 300 algal taxa identified on

, with

Bacillariophyceae Bacillariophyceae is a group of pennate diatoms with a raphe (raphids). According to Ruggiero et al., 2015, the diatoms are treated as follows. This treatment largely reflects that used by Algaebase as at 2015, and is also reflected in the current ...

(

Diatom A diatom (Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising sev ...

s) and Chlorophyta (

Green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

) being the most widespread on Antarctica. Diatoms are abundant in aquatic environments decreasing in number in terrestrial habitats. Chlorophyta are also important in mats in lakes and ponds but tend to increase their relative importance in terrestrial environments and especially in soils, where they are the densest algal group. Xanthophyceae (

Yellow-green algae Yellow-green algae or the Xanthophyceae (xanthophytes) are an important group of heterokont algae. Most live in fresh water, but some are found in marine and soil habitats. They vary from single-celled flagellates to simple colonial and filamento ...

) are an important component of the

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or '' skin flora''. E ...

in soils of Antarctica. Other algal groups ( Dinophyta, Cryptophyta, and

Euglenophyta Euglenids (euglenoids, or euglenophytes, formally Euglenida/Euglenoida, ICZN, or Euglenophyceae, ICBN) are one of the best-known groups of flagellates, which are excavate eukaryotes of the phylum Euglenophyta and their cell structure is typic ...

) are mainly limited to freshwater communities of the

Dry Valleys The McMurdo Dry Valleys are a row of largely snow-free valleys in Antarctica, located within Victoria Land west of McMurdo Sound. The Dry Valleys experience extremely low humidity and surrounding mountains prevent the flow of ice from nearby ...

species identified in recent research: *''

Hantzschia amphioxys ''Hantzschia amphioxys'' is a species of diatom belonging to the family Bacillariaceae. It has cosmopolitan distribution In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the ...

'' *'' Heterococcus moniliformis'' *'' Kentrosphaera facciolae'' *'' Luticola desmetii'' *'' Luticola doliiformis'' *'' Luticola evkae'' *''

Luticola muticopsis ''Luticola'' is a genus of marine diatoms. References

Naviculales Diatom genera {{Diatom-stub ...

'' *'' Luticola permuticopsis'' *'' Luticola tomsui'' *'' Monodus coccomyxa'' *'' Pinnularia borealis'' *''

Prasiola crispa ''Prasiola crispa'' is a small terrestrial green alga. Taxonomy The species, first described as ''Ulva crispa'' Lightfoot, is the type of the genus ''Prasiola.'' A lectotype was nominated for the species, the type location of which was provid ...

'' *'' Xanthonema bristolianum'' *'' Xanthonema exile''

Animals

Arthropods

Distribution of

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s is limited to areas of high soil moisture and/or access to water, such as streams, or snow meltwater.

Nematodes

Carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

appears to be more important than moisture in defining good habitats for

s in the

. '' Scottnema lindsayae'', a microbial feeder and the most abundant and widely distributed

metazoa Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in ...

, often occurs as the sole metazoan species in the McMurdo Dry Valleys. It makes its living eating

and

out in the dry, salty soils that dominate the valleys. All other

species are more abundant in moist or saturated soils where

and

are more abundant. Distribution of most

species is correlated negatively with elevation (due to temperature and precipitation) and

salinity Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal ...

, and positively with

soil moisture Soil moisture is the water content of the soil. It can be expressed in terms of volume or weight. Soil moisture measurement can be based on ''in situ'' probes (e.g., capacitance probes, neutron probes) or remote sensing methods. Water that enters ...

soil organic matter Soil organic matter (SOM) is the organic matter component of soil, consisting of plant and animal detritus at various stages of decomposition, cells and tissues of soil microbes, and substances that soil microbes synthesize. SOM provides numerous b ...

, and nutrient availability. '' Eudorylaimus'' spp. is the second most abundant

, followed by '' Plectus murrayi'' who are the least abundant

s. '' Plectus antarcticus'' eats

and prefers living in ephemeral streams. An average 2-pound bag of

dry valley A dry valley may develop on many kinds of permeable rock, such as limestone and chalk, or sandy terrains that do not regularly sustain surface water flow. Such valleys do not hold surface water because it sinks into the permeable bedrock. There ...

soils contains approximately 700

s, while the more fertile soil found at higher latitudes on the continent may contain approximately 4,000

Nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

species identified in recent research: *'' Amblydorylaimus isokaryon'' *'' Antarctenchus hooperi'' *''

Aphelenchoides hagueri ''Aphelenchoides'' is a genus of mycetophagous nematodes. Some species are plant pathogenic foliar nematodes. Taxonomy In 1961 Sanwal listed 33 species and provided a key. The most important species of these are ''Aphelenchoides ritzemabosi' ...

'' *'' Aphelenchoides helicosoma'' *'' Aphelenchoides vaughani'' *'' Calcaridorylaimus signatus'' *'' Ceratoplectus armatus'' *'' Chiloplacoides antarcticus'' *'' Chiloplectus masleni'' *'' Coomansus gerlachei'' *'' Cuticularia firmata'' *''

Ditylenchus ''Ditylenchus'' is a genus of plant pathogenic nematodes. References Tylenchida Secernentea genera Agricultural pest nematodes {{agri-stub ...

'' spp. **'' Ditylenchus parcevivens'' *'' Enchodelus signyensis'' *'' Eudorylaimus'' spp. **'' Eudorylaimus antarcticus'' **'' Eudorylaimus coniceps'' **'' Eudorylaimus glacialis'' **'' Eudorylaimus nudicaudatus'' **'' Eudorylaimus pseudocarteri'' **'' Eudorylaimus shirasei'' **'' Eudorylaimus spaulli'' **'' Eudorylaimus verrucosus'' *'' Eumonhystera vulgaris'' *'' Eutobrilus antarcticus'' *'' Geomonhystera antarcticola'' *'' Geomonhystera villosa'' *'' Mesodorylaimus'' spp. **'' Mesodorylaimus imperator'' **'' Mesodorylaimus signatus'' *'' Monhystera'' spp. *'' Panagrolaimus'' spp. **'' Panagrolaimus davidi'' **'' Panagrolaimus magnivulvatus'' *'' Paramphidelus'' spp. **'' Paramphidelus antarcticus'' *'' Plectus'' spp. **'' Plectus accuminatus'' **'' Plectus antarcticus'' **'' Plectus belgicae'' **'' Plectus frigophilus'' **'' Plectus insolens'' **'' Plectus meridianus'' **'' Plectus murrayi'' **'' Plectus tolerans'' *'' Rhabdblaimus'' spp. *'' Rhabditis krylovi'' *'' Rhyssocolpus paradoxus'' *'' Rotylenchus capensis'' *'' Scottnema lindsayae'' *'' Teratocephalus pseudolirellus'' *'' Teratocephalus rugosus'' *'' Teratocephalus tilbrooki'' *'' Tylenchus'' spp.

Rotifers

The three species listed below were found in

-dominated moist soils.

Rotifer The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John H ...

species identified in recent research: *'' Epiphanes'' spp. *''

Habrotrocha ''Habrotrocha'' is a genus of bdelloid rotifers. References Rotifer genera Bdelloidea {{rotifer-stub ...

'' spp. *'' Philodina'' spp.

Tardigrades

Tardigrade Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär ...

species identified in recent research: *'' Acutuncus antarcticus'' *'' Diphascon'' spp. (form. '' Adropoion'' spp.) **'' Diphascon alpinum'' **'' Diphascon dastychi'' **'' Diphascon polare'' **'' Diphascon tricuspidatum'' (form. '' Adropion tricuspidatum'') **'' Diphascon victoriae'' *'' Hypsibius'' spp. (form. '' Diphascon'' spp.) **'' Hypsibius alpinus'' **'' Hypsibius arcticus'' ** ''Hypsibius'' cfr ''mertoni simoizumii'' **''

Hypsibius convergens ''Hypsibius'' is a genus of tardigrades in the class Eutardigrada. Genome sequencing The genome of ''Hypsibius dujardini'' has been sequenced. ''Hypsibius dujardini'' has a compact genome and a generation time of about two weeks. It can be cult ...

'' **'' Hypsibius oberhaeseri'' **'' Hypsibius scoticus'' (form. '' Diphascon scoticus'') *''

Macrobiotus arcticus ''Macrobiotus'' is a genus of tardigrade Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze ...

'' *'' Macrobiotus cfr polaris'' *'' Macrobiotus mottai'' *'' Macrobiotus oberhauseri'' *'' Macrobiotus polaris'' *''

Minibiotus furcatus ''Minibiotus'' is a genus of tardigrades belonging to the family Macrobiotidae. The genus has almost cosmopolitan distribution. Species Species: *''Minibiotus acontistus'' *''Minibiotus aculeatus'' *''Minibiotus africanus'' References

...

'' *'' Ramajendas frigidus'' *''

Ramazzottius ''Ramazzottius'' is a genus of water bear or moss piglet, a tardigrade in the class Eutardigrada Eutardigrada are a class of tardigrades (Tardigrada) without lateral appendices. Primarily freshwater bound, some species have secondarily gained ...

'' spp. **'' Ramazzottius oberhauseri''

Bacteria

Typically, the highest numbers of cultured

are from relatively moist coastal soils, compared with the small bacteria communities of dry inland soils.

Cyanobacteria Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blu ...

are found in all types of aquatic habitats and often dominate the microbial biomass of streams and lake sediments. '' Leptolyngbya frigida'' is dominant in benthic mats, and is frequently found in soils and as an

es. ''Nostoc commune'' can develop to sizes visible to the naked eye if supplied with a thin water film. The genus ''

Gloeocapsa ''Gloeocapsa'' (from the Greek ''gloia'' (gelatinous) and the Latin ''capsa'' (case)) is a genus of cyanobacteria. The cells secrete individual gelatinous sheaths which can often be seen as sheaths around recently divided cells within outer shea ...

'' is one of the few cryptoendolithic taxa with a high adaptation to extreme environmental conditions in rocks of the

. Actinomycetota such as ''

Arthrobacter ''Arthrobacter'' (from the Greek, "jointed small stick”) is a genus of bacteria that is commonly found in soil. All species in this genus are Gram-positive obligate aerobes that are rods during exponential growth and cocci in their stationary ...

'' spp., '' Brevibacterium'' spp., and ''

Corynebacterium ''Corynebacterium'' () is a genus of Gram-positive bacteria and most are aerobe, aerobic. They are bacillus (shape), bacilli (rod-shaped), and in some phases of life they are, more specifically, club (weapon), club-shaped, which inspired the gen ...

'' spp. are prominent in the Dry Valleys. Thermophilic bacteria have been isolated from thermally heated soils near Mt. Melbourne and Mt. Rittman in northern

Victoria Land Victoria Land is a region in eastern Antarctica which fronts the western side of the Ross Sea and the Ross Ice Shelf, extending southward from about 70°30'S to 78°00'S, and westward from the Ross Sea to the edge of the Antarctic Plateau. It ...

. Bacteria genera found in both air samples and the

Antarctic The Antarctic ( or , American English also or ; commonly ) is a polar region around Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other ...

include ''

Staphylococcus ''Staphylococcus'' is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical (cocci), and form in grape-like clusters. ''Staphylococcus'' species are facultative ...

'', '' Bacillus'', ''

'', ''

Micrococcus ''Micrococcus'' (mi’ krō kŏk’ Əs) is a genus of bacteria in the Micrococcaceae family. ''Micrococcus'' occurs in a wide range of environments, including water, dust, and soil. Micrococci have Gram-positive spherical cells ranging from abo ...

'', '' Streptococcus'', '' Neisseria'', and '' Pseudomonas''. Bacteria were also found living in the cold and dark in a lake buried a half-mile deep () under the ice in

Bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

species identified in recent research: *'' Acinetobacter'' spp. *''

Alicyclobacillus acidocaldarius ''Alicyclobacillus acidocaldarius'' is a species of Gram positive, strictly aerobic, bacterium. The bacteria are acidophilic, thermophilic, and produce endospores. The first identified strains of ''A. acidocaldarius'' were from geysers in Yellow ...

'' *'' Aquaspirillum'' spp. *''

'' spp. *''

Azospirillum ''Azospirillum'' is a Gram-negative, microaerophilic, non- fermentative and nitrogen-fixing bacterial genus from the family of Rhodospirillaceae. ''Azospirillum'' bacteria can promote plant growth. Characteristics The genus ''Azospirillum'' b ...

'' spp. *'' Bacillus'' spp. **''

Bacillus fumarioli ''Bacillus fumarioli'' is a species of aerobic endospore-forming bacteria. It is moderately thermophilic A thermophile is an organism—a type of extremophile—that thrives at relatively high temperatures, between . Many thermophiles are ar ...

'' **'' Bacillus thermoantarcticus'' *'' Bizionia argentinensis'' *'' Brevibacterium'' spp. **'' Brevibacterium antarcticum'' *''

Brevundimonas The ''Brevundimonas'' are a genus of bacteria. They are Gram-negative, non-fermenting, aerobic bacilli. The ''Brevundimonas'' species are ubiquitous in the environment but are rarely isolated from clinical samples., although numbers are increasi ...

'' spp. *''

Chryseobacterium ''Chryseobacterium'' is a genus of Gram-negative bacteria. ''Chryseobacterium'' species are chemoorganotrophic, rod shape gram-negative bacteria. ''Chryseobacterium'' form typical yellow-orange color colonies due to flexirubin-type pigment. The g ...

'' spp. *''

Flavobacterium ''Flavobacterium'' is a genus of Gram-negative, nonmotile and motile, rod-shaped bacteria that consists of 130 recognized species. Flavobacteria are found in soil and fresh water in a variety of environments. Several species are known to cause ...

'' spp. *''

'' spp. *'' Hymenobacter roseosalivarius'' *'' Leptolyngbya frigida'' *'' Massila'' spp. *''

'' spp. *'' Modestobacter multiseptatus'' *'' Neisseria'' spp. *''

Nocardia ''Nocardia'' is a genus of weakly staining Gram-positive, catalase-positive, rod-shaped bacteria. It forms partially acid-fast beaded branching filaments (acting as fungi, but being truly bacteria). It contains a total of 85 species. Some spec ...

'' spp. *''

Nostoc commune ''Nostoc commune'' is a species of cyanobacterium in the family Nostocaceae. Common names include star jelly, witch's butter, mare's eggs, fah-tsai and facai. It is the type species of the genus ''Nostoc'' and is cosmopolitan in distribution. De ...

'' *'' Paenibacillus'' spp. *'' Planococcus'' spp. *''

Pseudonocardia antarctica ''Pseudonocardia antarctica'' is a bacterium from the genus of ''Pseudonocardia'' which has been isolated from soil from the McMurdo Dry Valleys from the Antarctica Antarctica () is Earth's southernmost and least-populated continent. Si ...

'' *'' Pseudomonas'' spp. *''

Psychrobacter ''Psychrobacter'' is a genus of Gram-negative, osmotolerant, oxidase-positive, psychrophilic or psychrotolerant, aerobic bacteria which belong to the family Moraxellaceae and the class Gammaproteobacteria. The shape is typically cocci or cocco ...

'' spp. *'' Sphingobacterium'' spp. *''

'' spp. *''

Stenotrophomonas ''Stenotrophomonas'' is a genus of Gram-negative bacteria, comprising at least ten species. The main reservoirs of Stenotrophomonas are soil and plants. ''Stenotrophomonas'' species range from common soil organisms (''S. nitritireducens'') to o ...

'' spp. *'' Streptococcus'' spp. *''

Streptomyces ''Streptomyces'' is the largest genus of Actinomycetota and the type genus of the family Streptomycetaceae. Over 500 species of ''Streptomyces'' bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, ...

'' spp.

Fungi

'' Chaetomium gracile'' is frequently isolated from geothermally heated soil on Mt. Melbourne in northern

. Fungi genera found in both air samples and the

include '' Penicillium'', '' Aspergillus'', ''

Cladosporium ''Cladosporium'' is a genus of fungi including some of the most common indoor and outdoor molds. Species produce olive-green to brown or black colonies, and have dark-pigmented conidia that are formed in simple or branching chains. Many species ...

'', '' Alternaria'', ''

Aureobasidium ''Aureobasidium'' is a genus of fungi belonging to the family Dothioraceae. The genus was first described by Pierre Viala and Gaston Boyer in 1891. Species The genus contains 26 species: *'' Aureobasidium aleuritis'' *'' Aureobasidium apocry ...

'', '' Botryotrichum'', ''

Botrytis Botrytis may refer to: * ''Botrytis'' (fungus), the anamorphs of fungi of the genus ''Botryotinia'' **''Botrytis cinerea'', a mold important in wine making *Botrytis, the cauliflower cultivar group of ''Brassica oleracea ''Brassica oleracea'' is ...

'', ''

Geotrichum Geotrichum is a genus of fungi found worldwide in soil, water, air, and sewage, as well as in plants, cereals, and dairy products; it is also commonly found in normal human flora and is isolated from sputum and feces. It was first described in ...

'', '' Staphylotrichum'', '' Paecilomyces'', and '' Rhizopus''.

Fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

species identified in recent research: *'' Alternaria'' spp. *'' Antarctomyces psychotrophicus'' *''

Arthrobotrys ferox ''Arthrobotrys'' is a genus of mitosporic fungi in the family Orbiliaceae. There are 71 species. They are predatory fungi that capture and feed on nematode worms. Rings that form on the hyphae constrict and entrap the worms, then hyphae grow in ...

'' *'' Aspergillus'' spp. **'' Aspergillus ustus'' *''

'' spp. *'' Botryotrichum'' spp. *''

'' spp. *'' Chaetomium gracile'' *'' Cadophora'' ssp. **'' Cadophora malorum'' *'' Cerrena unicolor'' *''

'' spp. **'' Cladosporium cladosporioides'' **''

Cladosporium herbarum ''Cladosporium herbarum'' is a common fungus found worldwide in organic and inorganic matter. It is efficiently distributed in the air, where it exists as the most frequently occurring fungal species. It can grow over a wide range of temperature ...

'' *'' Cochliobolus heliconiae'' *'' Coniochaeta ligniaria'' *''

Curvularia inaequalis ''Curvularia inaequalis'' is a plant saprobe that resides in temperate and subtropical environments. It is commonly found in the soils of forage grasses and grains. The species has been observed in a broad distribution of countries including Tu ...

'' *''

Debaryomyces ''Debaryomyces'' is a genus of yeasts in the family Saccharomycetaceae The Saccharomycetaceae are a family of yeasts in the order Saccharomycetales that reproduce by budding. Species in the family have a cosmopolitan distribution, and are pres ...

'' ssp. **''

Debaryomyces hansenii ''Debaryomyces hansenii'' is a species of yeast in the family Saccharomycetaceae. Also known as ''Candida famata'', it accounts for up to 2% of invasive candidiasis cases. Ecology ''Debaryomyces hansenii'' is an osmo-, halo- and xerotolerant ...

'' *'' Geomyces'' spp. **'' Geomyces pannorum'' (form. '' Chrysosporium pannorum'') *''

'' spp. *''

Hohenbuehelia ''Hohenbuehelia'' is a pleurotoid genus of agaric fungi characterized by gelatinous-sheathed bowling-pin-shaped cystidia, on conidia, basidiospore germ tubes, and mycelium that adhere to and capture nematodes. The fruitbodies bear thick-walled cy ...

'' spp. *'' Holwaya mucida'' *'' Mortierella antarctica'' *''

Mucor hiemalis ''Mucor hiemalis'' is among the zygosporic fungi found in unspoiled foods. It has different industrial importance as biotransforming agents of pharmacological and chemical compounds. Morphology and cell structure ''Mucor hiemalis'' grows in ex ...

'' *'' Paecilomyces'' spp. *'' Penicillium'' spp. **'' Penicillium jensenii'' **'' Penicillium swiecickii'' *''

Phaeosphaeria ''Phaeosphaeria'' is a genus of fungi in the family Phaeosphaeriaceae. It has about 95 species. The genus was circumscribed by Japanese mycologist Ichiro Miyake in 1909, with '' Phaeosphaeria oryzae'' assigned as the type species. Species *'' Ph ...

'' spp. *''

Phialophora ''Phialophora'' is a form genus of fungus with short conidiophores, sometimes reduced to phialides; their conidia are unicellular. They may be parasites (including on humans), or saprophytic (including on apples). Genetic analysis of ''Phialop ...

'' spp. **'' Phialophora fastigiata'' (form. '' Cadophora fastigiata'') *''

Phoma ''Phoma'' is a genus of common coelomycetous soil fungi. It contains many plant pathogenic species. Description Spores are colorless and unicellular. The pycnidia are black and depressed in the tissues of the host. ''Phoma'' is arbitrarily lim ...

'' spp. **''

Phoma herbarum ''Phoma herbarum'' is a fungal plant pathogen infecting various plant species, including ''Alchemilla vulgaris'', '' Arabis petraea'', '' Arenaria norvegica'', ''Armeria maritima'', ''Bartsia alpina'', ''Capsella bursa-pastoris'', ''Erysimum'', ...

'' *'' Rhizopus'' spp. *'' Rhizoscyphus ericae'' *'' Staphylotrichum'' spp. *'' Stereum hirsutum'' *'' Stictis radiata'' *'' Thelebolus microsporus'' *''

Trichophyton eboreum ''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are Mold (fungus), molds ...

Yeast

Yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

species identified in recent research: *'' Aureobasidium pullulans'' *'' Candida'' spp. **'' Candida psychrophilia'' *Species formerly referred to '' Cryptococcus'' **''

Naganishia albida ''Naganishia albida'' (synonym ''Cryptococcus albidus'') is a species of fungus in the family Filobasidiaceae. It is currently only known from its yeast state. The species was originally isolated from the air in Japan, and has subsequently been ...

'' **'' Vishniacozyma foliicola'' **'' Vishniacozyma victoriae'' **''

Naganishia vishniacii ''Naganishia vishniacii'' is an extremophile fungus originally isolated as a yeast from soil samples in the dry valleys of Antarctica. The species grows at 4 degrees Celsius and below but not at 26 degrees Celsius and above. Visually it is charac ...

'' *''

Leucosporidium antarcticum ''Leucosporidium'' is a genus of fungi found in the family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). T ...

'' *''

Leucosporidium scottii ''Leucosporidium'' is a genus of fungi found in the family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). T ...

'' *''

Rhodotorula ''Rhodotorula'' is a genus of pigmented yeasts, part of the division Basidiomycota. It is readily identifiable by distinctive orange/red colonies when grown on Sabouraud's dextrose agar (SDA). This distinctive color is the result of pigments ...

'' spp. **'' Rhodotorula laryngis'' **'' Rhodotorula minuta'' **''

Rhodotorula rubra ''Rhodotorula'' is a genus of pigmented yeasts, part of the division Basidiomycota. It is readily identifiable by distinctive orange/red colonies when grown on Sabouraud's dextrose agar (SDA). This distinctive color is the result of pigments ...

'' **'' Rhodotorula slooffiae'' *''

Trichosporon ''Trichosporon'' is a genus of anamorphic fungi in the family Trichosporonaceae. All species of ''Trichosporon'' are yeasts with no known teleomorphs (sexual states). Most are typically isolated from soil, but several species occur as a natural ...

'' spp. **'' Trichosporon beigelii'' **'' Trichosporon cutaneum''

Protozoa

The small amoebae are of two types. The most abundant are '' Acanthamoeba'' and ''

Echinamoeba Echinamoebidae is a family of Amoebozoa, containing the genera '' Echinamoeba'' and '' Filamoeba''. It was established by Frederick Page in 1975. Taxonomy Family Echinamoebidae Page 1975 * Genus '' Comandonia'' Sawyer & Griffin 1975 ex Pernin & ...

''. The second group consists of monopodal, worm-like amoebae, the

subcylindrical {{Short pages monitor