Ray spider
Theridiosomatidae, commonly known as ray spiders, are a family of araneomorph spiders first described by Eugène Simon in 1881. The family includes 137 species divided between 20 genera. 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
As of April 2023[update], the World Spider Catalog 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 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, Eocene
- †Eotheridiosoma Wunderlich 2004 Bitterfeld amber, Baltic amber, Eocene
- †Palaeoepeirotypus Wunderlich 1988 Dominican amber, Miocene
- †Umerosoma Wunderlich 2004 Baltic amber, Eocene
- †"Baalzebub" mesozoicum Penney 2014 - Vendée amber, France, Turonian later considered to be stem-theridiosomatid