Regional Color Patterns in the Parasitic Hymenoptera

Extract

Parasitic Hymenoptera in all parts of the world exhibit many striking color patterns. These patterns are differentiated into groups according to the locality, size and habits of the insect.

The really small species, i.e. those under 4 mm. long, can hardly be said to have a color pattern at all, and have virtually no regional differentiation anywhere except for a general prevalence of darker coloration in cool climates and paler in warm climates. In tropical regions many of the smaller Hymenoptera are confined to the shady interior of forests. These species often exhibit a disruptive pattern consisting of white spots at the tip of the antennae and the tip of the hind legs or ovipositor. These white spots show strikingly against a dark forest background and serve to draw attention away from the body of the insect itself. Such disruptive patterns are seldom found in temperate fhest species of the smallest sizes but are common in large sized forest-dwelling ichneumonids in all parts of the world.