''Aridulodrilus molesworthae'' is a large Australian

earthworm An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they we ...

occurring, unusually, in a semiarid region of

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

. It was recognised as a species of

Megascolecidae Megascolecidae is a family of earthworms native to Madagascar, Australia, New Zealand, Asia, and North America. At up to 2 meters in length, their large size distinguishes the Megascolecidae from other earthworm families. They are an essential par ...

, a family with extreme diversity in the wetter coastal regions of the continent, but distinguished as a new monotypic genus ''Aridulodrilus'', a name derived from Latin meaning a semi-desert worm. This animal was first recorded by a

Broken Hill Broken Hill is a city in the Far West (New South Wales), far west region of outback New South Wales, Australia. An inland mining city, it is near the border with South Australia on the crossing of the Barrier Highway (A32) and the Silver City Hi ...

property's manager, Rosalind Molesworth, after substantial rain had brought them to the surface; the specific epithet ''molesworthae'' honours its discoverer. As a species greater than 250 mm in length, it is considered to be a large earthworm, specimens may be up to 1.5 metres when extended. ''Aridulodrilus molesworthae'' is known at locations with low annual rainfall, an average of 260 mm, whereas most megascolecid species occur in areas receiving at least 400 mm rainfall

isohyet A contour line (also isoline, isopleth, isoquant or isarithm) of a function of two variables is a curve along which the function has a constant value, so that the curve joins points of equal value. It is a plane section of the three-dimensi ...

. Their diet of microscopic organisms within the soil, rather than vegetive matter near the surface, may allow the species to subsist in a more arid environment. They are unknown outside its type locality, an area of ten hectares, in the IBRA

Broken Hill Complex The Broken Hill Complex (code ''BHC''), an interim Australian bioregion, is located in both New South Wales and South Australia, and comprises an area of of inland Australia. IBRA 5.1 describes ''BHC'' as being: Hills and colluvial fans on P ...

region.

References

{{Taxonbar, from=Q110933110, from2=Q112189240 Megascolecidae Fauna of New South Wales Monotypic annelid genera