Hymenoptera means “membranous wings.” The third largest group in the class Insecta, this order includes ants, bees, wasps, horntails, and sawflies.
Little hooks, called hamuli, join the forewings and the smaller hindwings of these insects together. Both pairs of wings work cooperatively during flight. Most Hymenoptera have chewing mouthparts. Bees are the exception, with modified mouthparts and a proboscis for siphoning nectar. Hymenopteran antennae are bent like an elbow or knee, and they have compound eyes.
An ovipositor on the end of the abdomen allows the female to deposit eggs in host plants or insects. Some bees and wasps use a stinger, which is actually a modified ovipositor, to defend themselves when threatened. Females develop from fertilized eggs, and males develop from unfertilized eggs. Insects in this order undergo complete metamorphosis.
Two suborders divide the members of the order Hymenoptera. The suborder Apocrita includes ants, bees, and wasps. These insects have a narrow junction between the thorax and the abdomen, sometimes called the “wasp waist.” Entomologists group sawflies and horntails, which lack this characteristic, in the suborder Symphyta.
Habitat and Distribution:
Hymenopteran insects live throughout the world, with the exception of Antartica. Like most animals, their distribution is often dependent on their food supply. For example, bees pollinate flowers and require habitats with flowering plants.
Major Families in the Order:
Families and Genera of Interest:
- Genus Trypoxylon, the mud dauber wasps, are solitary wasps that collect and mold mud to form a nest.
- Sweat bees, the family Halictidae, are attracted to perspiration.
- Larvae of the family Pamphiliidae use silk to roll leaves into tubes or make webs; these sawflies are called leaf rollers or web spinners.
- Leaf-cutter ants of the genus Atta consume more Amazon rainforest vegetation than any other animal.