INSECTS
Wasps: Unnecessarily bad reputation
If a bee is a beneficial insect that produces honey and beeswax and pollinates flowers, a wasp is just a damned nuisance, right? Wrong! In fact, wasps can be beneficial on a plot as they kill an enormous number of other pests, including flies, caterpillars and, in some cases, cockroaches. Moreover, some wasps are important pollinators. Due to their high-energy needs, wasps also feed on nectar from a variety of flowers and are valuable pollinators in gardens and orchards. However, pollinator wasps are not likely to be found in Gauteng, as they more common to the arid and semi-arid regions of South Africa where certain types of fynbos flourish. Wasps belong to the
Hymenoptera insect order, along with over 100 000 other insects, including bees. Although there a many species of wasps, the wasps which are seen more often and which are more likely to build a nest where they are not welcome will exhibit similar physical characteristics. Adult wasps vary in length from 10 to 20 mm. The head is triangular in shape and has two compound eyes and a set of antennae. The wasp also has several single eyes referred to as ocelli. The most noticeable mouthparts are the mandibles, or jaws. These are hard curved appendages of considerable strength. The most noticeable difference between a bee and a wasp is the shape of the body. Wasps ' bodies are slender with a narrow waist connecting the thorax and abdomen, which, in the female houses the sting. Like all insects the wasp has six legs, which each have two joints, enabling flexibility, so that the wasp can grasp whatever it lands on. Two pairs of transparent wings are attached to the wasp ' s body at the thorax. The thin membranous appearance of the wings is what lends the wasp the classification of Hymenoptera. The other main difference between a bee and wasp is that the bee is furry, while the body of the wasp is smooth and hard. Colours of wasps vary from brown, white, black and yellow to brilliant metallic colours such as green, blue, red or combinations of these. Wasps are categorised as parasitic wasps, solitary hunting wasps and social wasps. Parasitic wasps lay their eggs in or on some insects. Often the mother will sting the hapless cockroach, spider, beetle, stick insect or caterpillar, but the insect does not die. The wasp larva develops on or inside the unfortunate host and once it has developed into a pupa it will eat the host. Some wasps also lay their eggs in the nests of bees or other wasps. When
Common wasp
the eggs hatch they feed on the host ' s egg or larva and then on the provision laid in for the host ' s larva. The egg of the cuckoo wasp is generally introduced into the host ' s cell whilst cell provisioning is taking place. In the case of the solitary hunting wasps, the female creates rearing cells in some sort of nest, goes out and collects prey that she
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