Tangle web spider

Tangle web spiders Fossil range: Cretaceous[1] - present
Enoplognatha ovata[2]
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Arachnida
Order:	Araneae
Superfamily:	Araneoidea
Family:	Theridiidae Sundevall, 1833
Genera
Achaearanea Anelosimus Argyrodes Cabello Cerocida Chrosiothes Chrysso Craspedisia Enoplognatha Episinus Hetschkia Latrodectus Paratheridula Spintharus Steatoda Stemmops Styposis Theridion Theridula Thwaitesia Tidarren Wirada many more
Diversity
109 genera, 2295 species

The tangle-web spiders (Theridiidae), also known as cobweb spiders and comb-footed spiders, are a large family (over 2200 species in over 100 genera)^[3] of three-dimensional space-web-builders found throughout the world. Theridiid spiders are entelegyne (have a genital plate in the female) araneomorph ecribellate (use sticky capture silk instead of woolly silk) spiders that often build tangle space webs and have a comb of serrated bristles (setae) on the tarsus of the fourth leg.

The family includes some model organisms for research, for example, the genus Latrodectus, the medically important widow spiders. In addition to studies characterizing their venom and its clinical manifestation, widow spiders are broadly used in research on spider silk, and on sexual biology including sexual cannibalism.

Anelosimus spiders are also model organisms, used for the study of sociality, its evolution, and its ecological and evolutionary causes and consequences. They are particularly important for such studies as the genus contains species varying from solitary to permanently social, and because sociality has evolved frequently within the genus allowing comparative studies across species. These spiders are also a promising model for the study of inbreeding as their mating system co-varies with sociality, and all permanently social species are highly inbred.

One species in Theridion, the Hawaiian T. grallator, is used as a model to understand the selective forces and the genetic basis of color polymorphism within species. Theridion grallator is known as the "happyface" spider, as certain morphs have a pattern uncannily resembling a smiley face or a grinning clown face on their yellow body.

The family also contains the well studied kleptoparasitic species of the subfamily Argyrodinae (including Argyrodes, Faiditus, and Neospintharus) which often have triangular bodies. These spiders live in the webs of larger spiders and pilfer small prey caught by their host's web, eat prey killed by the host spider, and may consume silk from the host web, as well as attack and eat the host itself.

The largest genus with over 600 species currently placed in it is Theridion, but it is not monophyletic. Another large genus is Parasteatoda, previously Achaearanea, which includes the common house spider.

Many theridiids trap ants and other ground dwelling insects by means of elastic sticky silk trap lines leading to the soil surface. Despite their name, cobweb or tangle-web spiders have a huge range of web architectures.

Systematics

Recent years have seen advances in the systematics of cobweb spiders with phylogenies reconstructed using both morphological and molecular data. The following classification is built on these results (see also Joel Hallan's Biology Catalog).

• Argyrodinae

• Argyrodes Simon, 1864
• Neospintharus Exline, 1950
• Ariamnes Thorell, 1869
• Deelemanella Yoshida, 2003
• Faiditus Keyserling, 1884
• Rhomphaea L. Koch, 1872
• Spheropistha Yaginuma, 1957

• Hadrotarsinae

• Anatea Berland, 1927
• Audifia Keyserling, 1884
• Dipoena Thorell, 1869
• Dipoenata Wunderlich, 1988
• Emertonella Bryant, 1945
• Euryopis Menge, 1868
• Eurypoena Wunderlich, 1992
• Gmogala Keyserling, 1890
• Guaraniella Baert, 1984
• Hadrotarsus Thorell, 1881
• Lasaeola Simon, 1881
• Phycosoma O. P.-Cambridge, 1879
• Yaginumena Yoshida, 2002
• Yoroa Baert, 1984

• Latrodectinae Petrunkevitch, 1928

• Crustulina Menge, 1868
• Latrodectus Walckenaer, 1805
• Steatoda Sundevall, 1833

• Pholcommatinae Simon, 1894

• Asygyna Agnarsson, 2006
• Carniella Thaler & Steinberger, 1988
• Cerocida Simon, 1894
• Craspedisia Simon, 1894
• Enoplognatha Pavesi, 1880
• Helvidia Thorell, 1890
• Pholcomma Thorell, 1869
• Phoroncidia Westwood, 1835
• Proboscidula Miller, 1970
• Robertus O. P.-Cambridge, 1879
• Selkirkiella Berland, 1924
• Styposis Simon, 1894
• Theonoe Simon, 1881
• Wirada Keyserling, 1886

• Sphintharinae

• Chrosiothes Simon, 1894
• Episinus Walckenaer, in Latreille, 1809
• Moneta O. P.-Cambridge, 1870
• Spintharus Hentz, 1850
• Thwaitesia O. P.-Cambridge, 1881
• Stemmops O. P.-Cambridge, 1894

• Theridiinae

• Achaearanea Strand, 1929
• Achaearyopa Barrion & Litsinger, 1995
• Ameridion Wunderlich, 1995
• Cabello Levi, 1964
• Cephalobares O. P.-Cambridge, 1870
• Chrysso O. P.-Cambridge, 1882
• Coleosoma O. P.-Cambridge, 1882
• Cyllognatha L. Koch, 1872
• Dipoenura Simon, 1908
• Echinotheridion Levi, 1963
• Exalbidion Wunderlich, 1995
• Helvibis Keyserling, 1884
• Histagonia Simon, 1895
• Jamaitidion Wunderlich, 1995
• Keijia Yoshida, 2001
• Macaridion Wunderlich, 1992
• Molione Thorell, 1892
• Neottiura Menge, 1868
• Nesticodes Archer, 1950
• Nipponidion Yoshida, 2001
• Paratheridula Levi, 1957
• Propostira Simon, 1894
• Rugathodes Archer, 1950
• Sardinidion Wunderlich, 1995
• Simitidion Wunderlich, 1992
• Takayus Yoshida, 2001
• Tekellina Levi, 1957
• Theridion Walckenaer, 1805
• Theridula Emerton, 1882
• Thymoites Keyserling, 1884
• Tidarren Chamberlin & Ivie, 1934
• Wamba O. P.-Cambridge, 1896

• incertae sedis

• Anelosimus Simon, 1891
• Astodipoena Petrunkevitch, 1958 † (fossil, Eocene)
• Chorizopella Lawrence, 1947
• Clya Koch & Berendt, 1854 † (fossil, Eocene)
• Coscinida Simon, 1895
• Eodipoena Petrunkevitch, 1942 † (fossil, Eocene)
• Eoysmena Petrunkevitch, 1942 † (fossil, Eocene)
• Flegia Koch & Berendt, 1854 † (fossil, Eocene)
• Hetschkia Keyserling, 1886
• Icona Forster, 1955
• Kochiura Archer, 1950
• Landoppo Barrion & Litsinger, 1995
• Marianana Georgescu, 1989
• Mictodipoena Petrunkevitch, 1958 † (fossil, Eocene)
• Municeps Petrunkevitch, 1942 † (fossil, Eocene)
• Nactodipoena Petrunkevitch, 1942 † (fossil, Eocene)
• Paidiscura Archer, 1950
• Tomoxena Simon, 1895
• Zercidium Benoit, 1977

Gallery

Cobweb spider.

Cobweb spider; ventral view.

See also

• List of Theridiidae species
• Spider families
• Theridiid webs

References

• Agnarsson I. 2006a. A revision of the New World eximius lineage of Anelosimus (Araneae, Theridiidae) and a phylogenetic analysis using worldwide exemplars. Zoological Journal of the Linnean Society 146: 453-593. PDF
• Agnarsson I. 2006b. Asymmetric female genitalia and other remarkable morphology in a new genus of cobweb spiders (Theridiidae, Araneae) from Madagascar. Biological Journal of the Linnean Society 87: 211-232. PDF
• Agnarsson I. 2006c. Phylogenetic placement of Echinotheridion (Araneae: Theridiidae) - do male sexual organ removal, emasculation, and sexual cannibalism in Echinotheridion and Tidarren represent evolutionary replicas? Invertebrate Systematics 20: 415-429. PDF
• Agnarsson I. 2004. Morphological phylogeny of cobweb spiders and their relatives (Araneae, Araneoidea, Theridiidae). Zoological Journal of the Linnean Society 141: 447-626. PDF
• Cooperative behavior of Anelosimus jabaquara (2002). PDF
• Arnedo, M.A., Coddington, J., Agnarsson, I. & Gillespie, R.G. (2004). From a comb to a tree: phylogenetic relationships of the comb-footed spiders (Araneae, Theridiidae) inferred from nuclear and mitochondrial genes. Molecular Phylogenetics and Evolution 31:225-245. PDF
• Arnedo MA, Agnarsson I, Gillespie RG. In Press. Molecular insights into the phylogenetic structure of the spider genus Theridion (Araneae, Theridiidae) and the origin of the Hawaiian Theridion-like fauna. Zoologica Scripta.
• Aviles, L., Maddison, W.P. and Agnarsson, I. 2006. A new independently derived social spider with explosive colony proliferation and a female size dimorphism. Biotropica, 38: 743-753.
• Benjamin, S.P. and Zschokke, S. 2003. Webs of theridiid spiders: construction, structure and evolution. Biological Journal of the Linnean Society, 78: 293-305.
• Blackledge, T.A., Swindeman, J.E. and Hayashi, C.Y. 2005. Quasistatic and continuous dynamic characterization of the mechanical properties of silk from the cobweb of the black widow spider Latrodectus hesperus. Journal of Experimental Biology, 208: 1937-1949.
• Blackledge, T.A. and Zevenbergen, J.M. 2007. Condition dependent spider web architecture in the western black widow Latrodectus hesperus. Animal Behaviour, 73: 855-864.
• Gillespie, R.G. and Tabashnik, B.E. 1994. Foraging Behavior of the Hawaiian Happy Face Spider (Araneae, Theridiidae). Annals of the Entomological Society of America, 87: 815-822.
• Gillespie, R.G. and Tabashnik, B.E. 1989. What makes a happy face? Determinants of color pattern in the Hawaiian happy face spider Theridion grallator (Araneae, Theridiidae). Heredity, 62: 355-364.
• Grostal, P. and Walter, D.E. 1997. Kleptoparasites or commensals? Effects of Argyrodes antipodianus (Araneae: Theridiidae) on nephila plumipes (Araneae: Tetragnathidae). Oecologia, 111: 570-574.
• Oxford, G.S. and Gillespie, R.G. 1996. Quantum shifts in the genetic control of a colour polymorphism in Theridion grallator (Araneae: Theridiidae), the Hawaiian happy-face spider. Heredity, 76: 249-256.
• Oxford, G.S. and Gillespie, R.G. 1996. Genetics of a colour polymorphism in Theridion grallator (Araneae: Theridiidae), the Hawaiian happy-face spider, from greater Maui. Heredity, 76: 238-248.
• Purcell, J. and Aviles, L. 2007. Smaller colonies and more solitary living mark higher elevation populations of a social spider. Journal of Animal Ecology, 76: 590-597.
• Vollrath, F. 1979. Behavior of the Kleptoparasitic Spider Argyrodes-Elevatus (Araneae, Theridiidae). Animal Behaviour, 27: 515-521.

External links

• Platnick, N.I. 2006. World Spider Catalog
• Key to several Theridiidae genera
• Tree of Life: Theridiidae
• Theridiidae research