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Ground Spiders and Allies - Superfamily: Gnaphosoidea
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Ground Spiders and their allies make up one of the largest groups comprising of 2,850 species in 199 genera spread over 7 families. Of these 78 species from 4 families may be found in the Northern Rivers so they make up a good part of our spider population. They have an almost world-wide distribution, only those areas with an extreme climate are devoid of them. Gnaphosoids do not spin webs for prey capture, the use of their silk is reserved mainly for shelter and reproductive purposes (eggsacs).
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As a superfamily the Gnaphosoidea have undergone considerable changes recently. the American arachnologist Norman I. Platnick (1951-2020) in particular, devoted much of his working life putting order into what was, historically, a jumbled mess. Unfortunately the task is not as yet complete and it is generally accepted that the group is not mono-phyletic meaning more work is needed. There are reasonable arguments based on certain morphological features, for the superfamily to split in two. This may still happen in the future.
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Spiders in this superfamily commonly range in size from small to medium with a some large species seen as well. Most common colours are: any shade of beige, reddish-brown, dark brown and black. Most are fairly evenly coloured - with the oft-seen darker abdomen - but there are also a handful of species with beautifully bold, patterned markings. All are hunting spiders that are mostly active at night and many have devoloped hunting techniques that allow them to overpower prey larger than themselves. During the day they tend to hide under rocks, fallen branches or other coarse debris where they may have built a small silken retreat for their own use.
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References and links:
> Azevedo, G.H.F., Bougie, T., Carboni, M., Hedin, M. and Ramírez, M.J., (2022). 'Combining genomic, phenotypic and sanger sequencing data to elucidate the phylogeny of the two-clawed spiders (Dionycha).' Molecular Phylogenetics and Evolution 166(107327): 1-14. doi:10.1016/j.ympev.2021.107327
> Nentwig, W. (ed.), (2013). 'Appendix : Spider Phylogeny.' Spider Ecophysiology, Springer, ISBN 978-3-642-33988-2
> Platnick, N.I., (2002). 'A revision of the Australasian ground spiders of the families Ammoxenidae, Cithaeronidae, Gallieniellidae, and Trochanteriidae (Araneae: Gnaphosoidea).' Bulletin of the American Museum of Natural History 271: 1-243. doi:10.1206/0003-0090(2002)271<0001:AROTAG>2.0.CO;2
> Ramírez, M., (2014). 'The morphology and phylogeny of Dionychan spiders (Araneae: Araneomorphae).' Bulletin of the American Museum of Natural History. 390 (390): 1–374. doi:10.1206/821.1. hdl:2246/6537. S2CID 86146467. pp. 323–327.
https://en.wikipedia.org/wiki/Ground_spider
https://www.arachne.org.au/01_cms/details.asp?ID=2218
http://www.bio.brandeis.edu/fieldbio/Spiders_Savransky_Suhd_Brondstatter/Pages/Fam_Gnaphosidae.html
> Azevedo, G.H.F., Bougie, T., Carboni, M., Hedin, M. and Ramírez, M.J., (2022). 'Combining genomic, phenotypic and sanger sequencing data to elucidate the phylogeny of the two-clawed spiders (Dionycha).' Molecular Phylogenetics and Evolution 166(107327): 1-14. doi:10.1016/j.ympev.2021.107327
> Nentwig, W. (ed.), (2013). 'Appendix : Spider Phylogeny.' Spider Ecophysiology, Springer, ISBN 978-3-642-33988-2
> Platnick, N.I., (2002). 'A revision of the Australasian ground spiders of the families Ammoxenidae, Cithaeronidae, Gallieniellidae, and Trochanteriidae (Araneae: Gnaphosoidea).' Bulletin of the American Museum of Natural History 271: 1-243. doi:10.1206/0003-0090(2002)271<0001:AROTAG>2.0.CO;2
> Ramírez, M., (2014). 'The morphology and phylogeny of Dionychan spiders (Araneae: Araneomorphae).' Bulletin of the American Museum of Natural History. 390 (390): 1–374. doi:10.1206/821.1. hdl:2246/6537. S2CID 86146467. pp. 323–327.
https://en.wikipedia.org/wiki/Ground_spider
https://www.arachne.org.au/01_cms/details.asp?ID=2218
http://www.bio.brandeis.edu/fieldbio/Spiders_Savransky_Suhd_Brondstatter/Pages/Fam_Gnaphosidae.html
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