Idiops

Front-eyed trapdoor spiders
Female I. castaneus
Male Idiops constructor in India
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Mygalomorphae
Family: Idiopidae
Genus: Idiops
Perty, 1833
Type species
I. fuscus
Perty, 1833
Species

96, see text

Synonyms
  • Acanthodon Guérin, 1838
  • Dendricon Octavius Pickard-Cambridge
  • O. Pickard-Cambridge, 1889 Juambeltzia
  • Cândido Firmino de Mello-Leitão Mello-Leitão, 1946
  • Pseudidiops Eugène Simon
  • Simon, 1889

Idiops is a genus of armored trapdoor spiders that was first described by Josef Anton Maximilian Perty in 1833. It is the type genus of the spurred trapdoor spiders, Idiopidae. Idiops is also the most species-rich genus of the family, and is found at widely separated locations in the Neotropics, Afrotropics, Indomalaya and the Middle East.

Distribution

Species of this genus are found in South America, Africa, South Asia and the Middle East.

Description

Females live in tubular burrows lined with a thick layer of white silk. These typically have a D-shaped lid that fits into the entrance like a cork, and some burrows have two entrances. The lid may consist of mud, moss or lichen, which is bound below by a thick layer of silk. As in all genera of this family, the anterior lateral eyes (ALE) are situated near the clypeal margin, far in front of the remaining six eyes, which are arranged in a tight group. The males which are smaller in size, wander about or occasionally live in burrows.

Body size ranges from 10 to 35 mm. The carapace is narrower posteriorly. The posterior eye row is procurved, and the median ocular area is widest posteriorly. The cheliceral fang furrows have equal rows of teeth along inner and outer margins. The sternum has only two pairs of sigilla marginally. The legs have coxae without spinules. The chelicerae are narrow, especially in males.

Life style

I. crassus and its trapdoor nest entrance

The burrows of Idiops are usually made in soil free of stones, which is soft during the rainy season but becomes very hard afterwards. The burrows are frequently made in open grassy plains with a gentle slope with low scrubs. The entrances are usually closed with a trapdoor that varies from cork-like to flat. The trapdoor has an outer surface that is well-camouflaged. It could be sand grains firmly stuck together so that it resembles the surface of the surrounding soil, grass tufts, or even dry black lichen.

Members of Idiops have been collected on various occasions in areas with high populations of the termite Hodotermes mossambicus. The males are frequently collected from pit traps.

Like other mygalomorphs, they are relatively large and long-lived. Forest clearance and agricultural practices that loosen the soil and enhance erosion, besides soil removal for brick making have been pointed out as serious threats to some Indian species. Species ranges are poorly known – in India for instance, most species are known only from their type localities.

Species

As of October 2025, this genus includes 86 species and one subspecies:

References

  1. 1 2 3 4 "Genus Idiops". World Spider Catalog. doi:10.24436/2. Retrieved 2025-10-02.
  2. ↑ Pickard-Cambridge, O. (1870). "Monograph of the genus Idiops, including descriptions of several species new to science". Proceedings of the Zoological Society of London. 38 (1): 107.
  3. ↑ Pocock, R. I. (1895). "Notes on the identity of some of the types of Mygalomorphae in the collection of the British Museum". Annals and Magazine of Natural History. 16 (6): 223. doi:10.1080/00222939508680262.
  4. ↑ Schiapelli, R. D.; Gerschman de P., B. S. (1971). "Estudio de algunas arañas descriptas por Mello-Leitão para el Uruguay". Revista de la Sociedad Entomológica Argentina. 33: 58.
  5. ↑ Raven, R. J. (1985). "The spider infraorder Mygalomorphae (Araneae): Cladistics and systematics". Bulletin of the American Museum of Natural History. 182: 158.
  6. ↑ Perty, M. (1833), "Arachnides Brasilienses", in de Spix, J. B.; Martius, F. P. (eds.), Delectus animalium articulatorum quae in itinere per Braziliam ann
  7. 1 2 Das, Sanjay Keshari; Khan, Ruhi Asra (December 2019). "A new trapdoor spider species of the genus Idiops Perty, 1833 (Araneae, Mygalomorphae, Idiopidae) from Odisha, India". Journal of Asia-Pacific Biodiversity. 12 (4): 678–681. doi:10.1016/j.japb.2019.09.002.
  8. 1 2 Mirza, Zeeshan; Sanap, Rajesh (April 2012). "A new species of the genus Idiops and notes on Idiops bombayensis Siliwal et al. 2005 (Araneae: Idiopidae) from Northern Western Ghats of Maharashtra, India". Journal of Arachnology. 40 (1): 85–95. doi:10.1636/A11-37.1. JSTOR 41804576. S2CID 85696927. Retrieved 27 June 2020.
  9. ↑ Jocque, R.; Dippenaar-Schoeman, A. S. (2007). Spider families of the world (PDF) (2nd ed.). Tervuren, Belgium: Musée royal de l'Afrique centrale. pp. 146–147. ISBN 978-90-74752-11-4.
  10. ↑ "New trapdoor spider species discovered". thehindu.com. The Hindu. 2 October 2019. Retrieved 27 June 2020.
  11. 1 2 3 Dippenaar-Schoeman, A.S.; Haddad, C.R.; Foord, S.H.; Lotz, L.N. (2021). The Idiopidae of South Africa. Version 1. South African National Survey of Arachnida Photo Identification Guide. p. 32. doi:10.5281/zenodo.6324502. This article incorporates text available under the CC BY 4.0 license.