Palystes castaneus

{{Short description|Species of spider}}

{{Speciesbox

| image = HuntsmanRSA.jpg

| image_caption =

| taxon = Palystes castaneus

| authority = Latreille, 1819

| synonyms =

• Ocypete melanogaster
• Ocypete nobilis
• Olios castaneus
• Olios fuscus
• Olios melanogaster
• Palystes chaperi
• Palystes frenatus
• Thomisus castaneus

}}

Palystes castaneus is a species of huntsman spider found in parts of South Africa.{{cite web|url=http://research.amnh.org/iz/spiders/catalog/SPARASSIDAE.html|title=Fam. Sparassidae|first=Norman I.|last=Platnick|authorlink=Norman I. Platnick|date=10 December 2011|work=The World Spider Catalog, Version 12.5|publisher=American Museum of Natural History|location=New York, NY, USA|doi=10.5531/db.iz.0001|accessdate=16 April 2012}} It is common from Cape Town to Heidelberg, Western Cape, especially in forested areas. In scrub outside forested areas, it is replaced by Palystes superciliosus. It occurs mainly on plants, where it hunts insects. It has a body length of 17–22 mm.{{cite web |url=http://www.biodiversityexplorer.org/arachnids/spiders/sparassidae/palystes_castaneus.htm |title=Palystes castaneus |first=Norman |last=Larsen |work=Biodiversity Explorer |publisher=Iziko museums |location=Cape Town, South Africa |accessdate=16 April 2012}} P. castaneus is the type species for the genus Palystes, and was first described by Pierre André Latreille in 1819.

Spiders in the genus Palystes are commonly called rain spiders, or lizard-eating spiders.{{cite web |url=http://www.biodiversityexplorer.org/arachnids/spiders/sparassidae/palystes.htm |title=Palystes |first=Norman |last=Larsen |work=Biodiversity Explorer |publisher=Iziko museums |location=Cape Town, South Africa |accessdate=16 April 2012}} P. castaneus often appears in the home just before the onset of rain, where they hunt geckos (usually Afrogecko porphyreus). Males are regularly seen from August to December, probably looking for females.

File:Palystes castaneus (Sparassidae egg purse IMG 2662.jpgAfter mating in the early summer, the female constructs a round egg sac about 60–100 mm in size made of silk, with twigs and leaves woven into it. These egg sacs are commonly seen from about November to April. The female 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. Many gardeners are bitten by protective Palystes mothers during this period. Females will construct about three of these egg sacs over their two-year lives.

File:Tachypompilus ignitus PompilidaeIMG 3672a.jpg dragging Palystes prey (not P. castaneus) up a wall]]P. castaneus (and other 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. The Pompilid wasp species Tachypompilus ignitus is at least largely a specialist hunter of mature Palystes females.{{cite book |first1=Mike |last1=Picker |author1-link=species:Mike D. Picker |first2=Charles |last2=Griffiths |author2-link=species:Charles L. Griffiths |first3=Alan |last3=Weaving |title=Field Guide to Insects of South Africa |edition=Updated |year=2004 |publisher=Struik |location=Cape Town, South Africa |isbn=978-1-77007-061-5 |oclc=56338396 |page=402}}