''Scottnema lindsayae'' is a species of nematode belonging to the family

Cephalobidae Cephalobidae is a family of nematodes belonging to the order Rhabditida. Genera Genera: * ''Acrobeles'' von Linstow, 1877 * ''Acrobeloides'' Cobb, 1924 * ''Scottnema'' Timm, 1971 References

{{Taxonbar, from=Q5266809 Nematodes ...

. First described in 1971, it is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to Antarctica and most commonly found in the

McMurdo 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 ...

. ''S. lindsayae'', a microscopic worm, feeds on microbes, including bacteria, yeast, and algae. Adapted to very cold and dry climates, its population may be decreasing as a result of climate change.

Taxonomy

''S. lindsayae'' is the only described member of ''Scottnema''. Originally described by R. W. Timm (1971), it was named after the polar explorer Robert Scott and the collector of the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

specimen, Kay Lindsay.

Description and lifecycle

''S. lindsayae'' is between half a millimeter and a millimeter in length and between two and four

micrometers The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

in width. ''S. lindsayae'' reproduces sexually, with females laying eggs. The minimum observed lifecycle length at is 218 days, with four juvenile stages outside of the egg. As it enters hibernation during Antarctic winters, ''S. lindsayae'' likely needs more than one summer to complete one lifecycle. Temperatures above were harmful to its reproductive cycle, with development being significantly impaired at . As a result, significantly warming temperatures in Antarctic may pose a threat to this species. In 2006, the population had decreased by 65% since 1993.

Habitat

''S. lindsayae'' is one of three nematodes found in the soil of the McMurdo Dry Valleys, and the only one endemic to the continent. It has also been found in other parts of Antarctica, including

East Ongul Island East Ongul Island is an island in the Flatvaer Islands off of Antarctica. It is long, lying immediately east of the northern part of Ongul Island at the east side of the entrance of Lutzow-Holm Bay. East Ongul Island this island was originally ...

and Admiralty Bay. In the dry valleys, ''S. lindsayae'' is the dominant nematode, representing about 80% of the worms recorded, especially in the colder and drier parts where other species often cannot be found. It is also more common at higher altitudes. Found as far south as 83.48 degrees, it is the southernmost worm species recorded.

References

{{Taxonbar, from=Q21299221 Rhabditida Fauna of Antarctica Nematodes described in 1971 Species endangered by climate change