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Deinopis

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Deinopis
Deinopis subrufa
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Deinopidae
Genus: Deinopis
MacLeay, 1839[1]
Type species
D. lamia
MacLeay, 1839
Species

51, see text

Deinopis, also known as net-casting spiders, gladiator spiders and ogre-faced spiders,[2] is a genus of net-casting spiders that was first described by W. S. MacLeay in 1839.[3] Its distribution is widely tropical and subtropical. They catch their prey using a specially spun "net". The name is derived from the Greek δεινός (deinos), meaning "fearful", and opis, meaning "appearance", referring to their ogre-like faces. The spelling "Dinopis" is also found, but is regarded as an "unjustified emendation".[4]

Net-casting

Spiders in the genus Deinopis catch their prey in an unusual fashion. They first spin a small upright rectangular cribellate web. This is then detached from its supporting threads and held horizontally above the ground by the spider's long front two pairs of legs while the spider hangs almost vertically. Passing prey is then captured by dropping the "net" over it.[2]

Eyes

The two posterior median eyes are enlarged and forward-facing.[5] These eyes have a wide field of view and are able to gather available light more efficiently than the eyes of cats and owls. This is despite the fact that they lack a reflective layer (tapetum lucidum); instead, each night, a large area of light-sensitive membrane is manufactured within the eyes, and since arachnid eyes do not have irises, it is rapidly destroyed again at dawn. To aid further in netting prey, the spider places white fecal spots on the surface below the net and uses them for aiming.[6] The spiders also lack ears and use hairs and receptors on their legs to distinguish sounds at a distance of up to 2 meters.[7] [8]

Species

As of May 2019 it contains fifty-one species:[1]

References

  1. ^ a b Gloor, Daniel; Nentwig, Wolfgang; Blick, Theo; Kropf, Christian (2019). "Gen. Deinopis MacLeay, 1839". World Spider Catalog Version 20.0. Natural History Museum Bern. doi:10.24436/2. Retrieved 2019-05-31.
  2. ^ a b Leong, T.M. & Foo, S.K. (2009), "An encounter with the net-casting spider, Deinopis species in Singapore (Araneae: Deinopidae)" (PDF), Nature in Singapore, 2: 247–255, retrieved 2015-09-28
  3. ^ MacLeay, W. S. (1839). "On some new forms of Arachnida". Annals of Natural History. 2 (7): 1–2.
  4. ^ "Gen. Deinopis MacLeay, 1839", World Spider Catalog, Natural History Museum Bern, retrieved 2015-09-28
  5. ^ Culver, Jordan. "Ogre-faced spiders don't need ears to 'hear' their prey, study finds. These large-eyed nocturnal predators snag food out of the air". USA TODAY. Retrieved 2020-12-27.
  6. ^ "How spiders see the world". Australian Museum. 2015-10-30. Retrieved 2016-09-07.
  7. ^ Press, Cell (2020-10-31). "Ogre-Faced Spiders: These Spiders Can Hear – Even Though They Have No Ears". SciTechDaily. Retrieved 2020-12-27.
  8. ^ "Ogre-faced spiders have great hearing—without ears". Animals. 2020-10-29. Retrieved 2020-12-27.

External links