''Anelosimus pratchetti'' is a species of
tangle-web spider
Theridiidae, also known as the tangle-web spiders, cobweb spiders and comb-footed spiders, is a large family of araneomorph spiders first described by Carl Jakob Sundevall in 1833. This diverse, globally distributed family includes over 3,000 ...
found in
New South Wales,
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
. Initial field observations indicate it is a
subsocial spider. It lives in low elevation environments, including beachfront mangrove forests. It was identified by Ingi Agnarsson in 2012, who named the species after
Terry Pratchett, whom Agnarsson described as "a comic genius".
Description
The total length of the spider is approximately , with females slightly larger than the males. The colouration pattern is similar to others in its genus: the prosoma is light yellow with grey lines, while the
abdomen is lighter in colour with spots clustering off the midline.
Its primary diagnostic characteristic is the shape of the genitals. In males, the
embolus is corkscrew-shaped. A similar shape is found in ''
Anelosimus luckyi
''Anelosimus luckyi'' is a species of spider found in Papua New Guinea. It is known only from the holotype specimen, found by Andrea Lucky in 2009 and after whom the species is named. It was discovered in Western Province at an elevation of ...
'', although the embolus is longer in ''A. pratchetti''. The female can be distinguished from others in the genus by the shape of the copulatory ducts and a unique triangular epigynal plate.
Distribution and genetics
The holotype specimen was collected from
Berowra Valley Regional Park
The Berowra Valley Regional Park is in the Hornsby Shire in Sydney, Australia. Most of what was previously the regional park was placed in the Berowra Valley National Park in September 2012. Only a small portion remains as the regional park.
S ...
, at an elevation of approximately . Additional specimens have been collected from
Toolijooa
Toolijooa is a small village in the Municipality of Kiama, Illawarra, New South Wales, Australia.
Transport
It lies on the South Coast railway line, and once had a railway station
Rail transport (also known as train transport) is a mean ...
at elevations of approximately . The species has only been found in Australia. The holotype and several paratypes were curated by the
National Museum of Natural History.
The species uniqueness and placement in the genus has been confirmed by analysis of nuclear and mitochondrial DNA. Phylogenetic analysis indicates a closer link between ''Anelosimus pratchetti'' and two
Madagascar species, ''
Anelosimus sallee'' and ''
Anelosimus may
''Anelosimus'' is a cosmopolitan genus of cobweb spiders (Theridiidae), currently containing 74 species. ''Anelosimus'' is a key group in the study of sociality and its evolution in spiders (Aviles 1997). It contains species spanning the spectr ...
'', than several geographically closer species within the same genus.
The species on Madagascar have previously been identified as arriving in multiple migration events. The finding further illustrates the complexity of migration within the genus.
Sociality
Spiders within the genus ''Anelosimus'' have been studied due to their social structure. Most of the species within the genus are social or subsocial, with solitary species in the genus occurring within a single clade. Not all species within the clade are solitary, however, indicating a reversal within the clade.
Two species closely related to ''A. pratchetti'', ''A. may'' and ''A. sallee'', have both been identified as subsocial.
Preliminary observations on ''A. pratchetti'' indicate it is subsocial as well.
References
{{Taxonbar, from=Q16748575
Theridiidae
Spiders of Australia
Spiders described in 2012
Terry Pratchett