Deinopis

Etymology

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".

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.

Eyes

The two posterior median eyes are enlarged and forward-facing. These eyes have a wide field of view and are able to gather available light more efficiently than the eyes of cats and owls, and are 2000 times more sensitive to light than human photoreceptors. 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 destroyed at dawn, with the membrane being converted into vesicles which are then lysed in the inter-rhabdomeral cytoplasm.

To aid further in netting prey, the spider places white fecal spots on the surface below the net and uses them for aiming. Spiders also lack ears, but Deinopis use hairs and receptors (slit sensillae) on their legs to distinguish sounds at a distance of up to 2 meters.

Species

, this genus includes twenty species:

• Deinopis amica Schiapelli & Gerschman, 1957 – Argentina, Uruguay
• Deinopis armaticeps Mello-Leitão, 1925 – Brazil
• Deinopis biaculeata Simon, 1906 – Brazil
• Deinopis bituberculata Franganillo, 1930 – Cuba
• Deinopis bucculenta Schenkel, 1953 – Venezuela
• Deinopis cylindracea C. L. Koch, 1846 – Colombia
• Deinopis diabolica Kraus, 1956 – El Salvador
• Deinopis fastigata Simon, 1906 – Brazil
• Deinopis granadensis Keyserling, 1879 – Colombia
• Deinopis guasca Mello-Leitão, 1943 – Brazil
• Deinopis guianensis Taczanowski, 1874 – French Guiana
• Deinopis lamia MacLeay, 1839 – Cuba, Turks & Caicos, Puerto Rico (type species)
• Deinopis longipes F.O. Pickard-Cambridge, 1902 – Mexico, Panama
• Deinopis pallida Mello-Leitão, 1939 – Brazil
• Deinopis pardalis Simon, 1906 – Brazil
• Deinopis plurituberculata Mello-Leitão, 1925 – Brazil
• Deinopis rodophthalma Mello-Leitão, 1939 – Brazil
• Deinopis seriata Simon, 1906 – Brazil
• Deinopis spinosa Marx, 1889 – United States, Jamaica, St. Vincent, Venezuela
• Deinopis tuboculata Franganillo, 1926 – Cuba

References

References

1. "Genus Deinopis". World Spider Catalog.
2. (2015-10-30). "How spiders see the world". [[Australian Museum]].
3. (2020-10-29). "Ogre-faced spiders have great hearing—without ears".
4. . (2020-10-31). ["Ogre-Faced Spiders: These Spiders Can Hear – Even Though They Have No Ears"](https://scitechdaily.com/ogre-faced-spiders-these-spiders-can-hear-even-though-they-have-no-ears/).
5. (1978). "The rapid synthesis and destruction of photoreceptor membrane by a dinopid spider: A daily cycle". Proceedings of the Royal Society of London. Series B. Biological Sciences.
6. (2022). "Biogeography and eye size evolution of the ogre-faced spiders". Scientific Reports.
7. 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.".
8. (2009). "An encounter with the net-casting spider, ''Deinopis'' species in Singapore (Araneae: Deinopidae)". Nature in Singapore.
9. MacLeay, W. S.. (1839). "On some new forms of Arachnida.". Annals of Natural History.