Black and White Kite spider

Box kite spiders is a common name for the Afrotropical Isoxya genus of orb-weaver spiders. Like the Spiny orb-weavers they have six prominent (but short) spines on their abdomen. They are small spiders, measuring 3 to 7 mm across. They have a sclerotised (or porcelain-like) abdomen which is typical of the Gastricanthinae.
Five species are known in South Africa