There is a genus of stone-nest spiders, in Afrikaans klipnessiespinnekoppe and scientifically known as Nemoscolus that spin silky retreats, stone-enhanced as they are equipped with nifty building skills.
The nests are suspended in the air from near the middle of their webs, from where they monitor the arrivals and web entanglements of edible visitors like grasshoppers and other jumping insects. Eating at home is so convenient if one’s favourite food comes hopping along.
About four of the 15 Nemoscolus species occur in South Africa, including Nemoscolus cotti, the banded stone-nest spider, N. tubicola, the tube stone-nest spider and N. vigintipunctatus, the spotted stone-nest spider.
These spiders range from cream-coloured to black, each species in a particular pattern. Their bodies are somewhat elongated, the abdomens rounded to oval and the legs held closely against the bodies. The males are slightly smaller (Wikipedia; www.arc.agric.za; http://www.saeon.ac.za).