Palystes

Palystes
Female Palystes castaneus near Somerset West, South Africa
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Section: Entelegynae
Family: Sparassidae
Genus: Palystes
L. Koch, 1875
Type species
Palystes castaneus
Latreille, 1819
Species

See text.

Diversity[1]
22 species

Palystes is a genus of huntsman spiders, commonly called rain spiders or lizard-eating spiders,[2] occurring in Africa, India, Australia, and the Pacific.[1] The most common and widespread species is P. superciliosus, found in South Africa, home to 12 species in the genus.[1][2] The name Palystes is derived from either the Latin palaestes or the Greek palaistes, meaning "wrestler".[2] The genus was first described by Ludwig Carl Christian Koch in 1875.[1]

Build

Palystes are large spiders, with a body length of 15–36 mm, and a leg span of up to 110 mm. Their top side is covered in tan to dark tan velvety setae (hairs). The underside of their legs is banded in colour, and their legs and abdomens may be interspersed with slightly longer setae. They have a large moustachial stripe below their front eyes, and extending down their fangs.[2]

Habits

While Palystes mostly hunt insects on plants, they commonly enter houses before rain, or during the summer, where they will prey on geckos (usually Afrogecko porphyreus in the Western Cape, or Lygodactylus capensis in the eastern parts of southern Africa). Males are regularly seen from August to December, probably looking for females.[2]

Egg sac of P. castaneus

The large round egg sacs of P. castaneus and P. superciliosus are commonly seen from about November to April. After mating in the early summer, the female makes a 60–100 mm sac out of silk, with twigs and leaves woven into it. She constructs the sac over 3–5 hours, then aggressively guards it until the spiderlings, who hatch inside the protective sac, chew their way out about three weeks later. Females will construct about three of these egg sacs over their two-year lives. Many gardeners are bitten by protective Palystes mothers during this period.[2]

Venom

The size of Palystes spiders, combined with the banding on the underside of the legs exposed when the spider is in threat pose, give them a fearsome appearance.[2][3] An experiment was done in 1959 where a P. superciliosus was allowed to bite an adult guinea pig on the nose. The guinea pig died within 7 minutes, leading to a belief that the spider's venom was dangerous. However, further research on anaesthetized guinea pigs showed that the original guinea pig had actually died of shock, rather than as a result of the spider's venom.[3] In humans a Palystes bite is no more dangerous than a bee sting.[2] It causes a burning sensation, and swelling which lasts for a few days. Recovery is spontaneous and complete.[3]

Tachypompilus ignitus dragging Palystes prey up a wall

Wasps

Palystes spiders are also commonly seen paralysed, being dragged by a large wasp called a Pompilid wasp. Sometimes the wasp will not be present. Pompilid wasps only hunt spiders, which they paralyse by stinging them. They then drag the spider back to their nest where they lay an egg on the spider, then seal the spider and the egg in. When the egg hatches, the larva eats the paralysed spider, keeping the spider alive as long as possible by eating peripheral flesh first, and saving the vital organs till last. By doing this, the spider stays fresh long enough for the wasp larva to mature and pupate.[2] The Pompilid wasp species Tachypompilus ignitus is at least largely a specialist hunter of mature Palystes females.[4]

Species

According to The World Spider Catalog, Version 12.5:[1]

References

  1. 1 2 3 4 5 Platnick, Norman I. (10 December 2011). "Fam. Sparassidae". The World Spider Catalog, Version 12.5. New York, NY, USA: American Museum of Natural History. doi:10.5531/db.iz.0001. Retrieved 19 April 2012.
  2. 1 2 3 4 5 6 7 8 9 Larsen, Norman. "Palystes (rain spiders, lizard-eating spiders)". Biodiversity Explorer. Cape Town, South Africa: Iziko museums. Retrieved 19 April 2012.
  3. 1 2 3 Snyman, C.; Larsen, N. (March–April 2005). "Spider bite and its treatment in southern Africa" (PDF). Occupational Health Southern Africa. Kloof, South Africa: Technique Publishing. 11 (2): 22–26. ISSN 1024-6274. OCLC 80013902. Retrieved 19 April 2012.
  4. ↑ Picker, Mike; Griffiths, Charles; Weaving, Alan (2004). Field Guide to Insects of South Africa (Updated ed.). Cape Town, South Africa: Struik. p. 402. ISBN 978-1-77007-061-5. OCLC 56338396.
  5. ↑ Jäger, P. and D. Kunz. (2010). Palystes kreutzmanni sp. n. – a new huntsman spider species from fynbos vegetation in Western Cape Province, South Africa (Araneae, Sparassidae, Palystinae). ZooKeys 67 1-9.
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