The Lake Pedder earthworm (''Hypolimnus pedderensis'') is an extinct

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. T ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Megascolecidae The Megascolecidae is a taxonomic family of earthworms which is native to Madagascar, Australia, New Zealand and both South East Asia and North America. All species of Megascolecidae belong to the Clitellata class. Megascolecidae are a large fami ...

. Its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

''Hypolimnus'' is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

. It was

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 else ...

to the

Lake Pedder Lake Pedder, once a glacial outwash lake, is a man-made impoundment and diversion lake located in the southwest of Tasmania, Australia. In addition to its natural catchment from the Frankland Range, the lake is formed by the 1972 damming of the ...

area in

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

, Australia, prior to its flooding in 1972 for a hydro-electric power scheme. It is only known from a specimen collected from a Lake Pedder beach in 1971. Listed as Extinct (EX v2.1) A 1996 survey failed to find it and it is presumed extinct. The Lake Pedder earthworm mainly fed on microbes or algae on sand particles. Their feeding habits were seen to have a considerable impact on the banks of the lake, as the particles they consumed were deposited on the surface of the ground in the form of castings. As these castings were exposed to air, the soil was aerated, improving both the drainage and water holding capacity of the soil.

References

Megascolecidae Extinct animals of Australia Lake Pedder Endemic fauna of Australia Taxonomy articles created by Polbot Animals described in 1974 {{Annelid-stub