Introduction

Abstract

Abstract Gold wasps or cuckoo wasps are common names often applied to the family Chrysididae. Their frequently metallic coloration justifies the former, and cleptoparasitic habits refer to the latter. This brilliant aspect is best observed on a sunny day as the female wasp is searching a nesting site of a favoured wasp host. The sunlight reflects from the parasite and seems to accentuate the metallic colours—blue, green, purple, red, copper, brass, and gold—in various combinations. Most chrysidids are small and, although not all are brilliant, the tiny ones often make up for in colour what they lack in size. The sight of a Hedychridium moving erratically over the sand like a drop of pure gold never fails to astonish the collector. In the Western Hemisphere most chrysidids are metallic blue, green, and purple, in various combinations. In the old world, especially in the southern USSR and Africa, these wasps are often more colourful. A single specimen may be green, blue, purple, copper, gold, and red; all somewhat iridescent. These are interference colours. The true pigment shades of red, brown, and white are not so common. In addition to the often bright integument are the myriads of tiny impressions or punctures which are nearly always present. These modify and often enhance the coloration.