Theridiosomatidae, commonly known as ray spiders, are a family of

araneomorph The Araneomorphae (also called the Labidognatha or "true spiders") are an infraorder of spiders. They are distinguishable by chelicerae (fangs) that point diagonally forward and cross in a pinching action, in contrast to the Mygalomorphae (taran ...

spiders Spiders (order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species di ...

first described by

Eugène Simon Eugène Louis Simon (; 30 April 1848 – 17 November 1924) was a French naturalist who worked particularly on insects and spiders, but also on birds and plants. He is by far the most prolific spider Taxonomy (biology), taxonomist in history, ...

in 1881. The family includes 137

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

divided between 20

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

. They are most recognizable for their construction of cone-shaped webs. The cephalothorax of Theridiosomatidae includes one pair of labio-sternal glands which seems a characteristic of the family and could be considered as a variation of segmental glands opening on the base of prosomatic appendages in various Spiders. This organ is composed of a cuticular sack-like reservoir opening on the sternum via a "pit", and of a cluster of functional units belonging to the class 3 of arthropodian epidermal glands. Each unit includes a large adenocyte provided with characteristic foliaceous microvilli (heart-shaped in Naatlo) and numerous mitochondria, an excretory duct terminating to a pore (located on an "apophysis" in Wendilgarda) and canal cells. Present in immature and both sexes, the labiosternal gland elaborates a golgian semiochemical, either a pheromone for intraspecific communication, or an allomone improving the prey capture.Labiosternal glands were discovered and named by André Lopez(1985,1988,1993)(external link :"archentoflor")

Genera

, the

World Spider Catalog The World Spider Catalog (WSC) is an online searchable database concerned with spider taxonomy. It aims to list all accepted families, genera and species, as well as provide access to the related taxonomic literature. The WSC began as a series of ...

accepts the following genera: *'' Andasta'' Simon, 1895 – Seychelles, Malaysia, Sri Lanka *'' Baalzebub'' Coddington, 1986 – Central America, Brazil, Australia, China *'' Chthonopes'' Wunderlich, 2011 – Laos *'' Chthonos'' Coddington, 1986 – Ecuador, Brazil, Peru *'' Coddingtonia'' Miller, Griswold & Yin, 2009 – Malaysia, Laos *'' Cuacuba'' Prete, Cizauskas & Brescovit, 2018 *'' Epeirotypus'' O. Pickard-Cambridge, 1894 – Mexico, Costa Rica *'' Epilineutes'' Coddington, 1986 – Mexico, Brazil *'' Karstia'' Chen, 2010 – China *'' Menglunia'' Zhao & Li, 2012 – China *'' Naatlo'' Coddington, 1986 – Central America, South America, Trinidad and Tobago *'' Ogulnius'' O. Pickard-Cambridge, 1882 – South America, Caribbean, Panama, Asia *'' Parogulnius'' Archer, 1953 – United States *''

Plato Plato ( ; Greek language, Greek: , ; born BC, died 348/347 BC) was an ancient Greek philosopher of the Classical Greece, Classical period who is considered a foundational thinker in Western philosophy and an innovator of the writte ...

'' Coddington, 1986 – South America, Trinidad *'' Sennin'' Suzuki, Hiramatsu & Tatsuta, 2022 – Japan *'' Sinoalaria'' Zhao & Li, 2014 – China *'' Tagalogonia'' Labarque & Griswold, 2014 – Philippines *'' Theridiosoma'' O. Pickard-Cambridge, 1879 – South America, Africa, Oceania, North America, Asia, Central America, Jamaica *'' Wendilgarda'' Keyserling, 1886 – Asia, São Tomé and Príncipe, Central America, Brazil, Mexico, Caribbean *'' Zoma'' Saaristo, 1996 – China, Seychelles

Fossil species

* †''Eoepeirotypus'' Wunderlich 2004

Baltic amber Baltic amber or succinite is amber from the Baltic region, home of its largest known deposits. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that this forested region provided the re ...

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

* †''Eotheridiosoma'' Wunderlich 2004 Bitterfeld amber, Baltic amber, Eocene * †''Palaeoepeirotypus'' Wunderlich 1988

Dominican amber Dominican amber is amber from the Dominican Republic derived from resin of the extinct tree '' Hymenaea protera''. Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has a higher number of fossil in ...

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

* †''Umerosoma'' Wunderlich 2004 Baltic amber, Eocene * †"''Baalzebub''" ''mesozoicum'' - Vendée amber, France,

Turonian The Turonian is, in the International Commission on Stratigraphy, ICS' geologic timescale, the second age (geology), age in the Late Cretaceous epoch (geology), Epoch, or a stage (stratigraphy), stage in the Upper Cretaceous series (stratigraphy), ...

later considered to be stem-theridiosomatid

References

External links

*https://www.archentoflor.com/araignee%20labiosternale.html Spiders of South America Theridiosomatidae {{Theridiosomatidae-stub

Genera

Fossil species

See also

References

External links