The egg — larva — pupa — adult lifecycle, or complete metamorphosis, is famous in the world of insects. Some well-known insect orders, such as Lepidoptera (butterflies and moths), Coleoptera (beetles), Diptera (flies), and Hymenoptera (bees, wasps, and ants) undergo this process. Many other orders of insects, however, grow through what is known as incomplete metamorphosis, or hemimetabolism. In this lifecycle, once the egg hatches, the young insect generally resembles a miniature version of the adult. As it grows, it molts, each time getting a little larger. These sub-adult insects are known as instars. In the final molt, wings are usually grown, and the insect has reached its adult form. There is no pupal stage in incomplete metamorphosis.
Familiar insects that grow this way include Orthoptera (grasshoppers, crickets, and katydids), Mantodea (mantises), and Hemiptera (true bugs, aphids, leafhoppers, cicadas, et. al.). Many aquatic insects are also in this group: Odonata (dragonflies and damselflies), Ephemeroptera (mayflies), and Plecoptera (stoneflies).
This morning I had the pleasure of spotting a tiny katydid instar walking about on one of our small agaves. I believe it’s Microcentrum rhombifolium, the greater angle-wing katydid. It spent some time preening one of its (excessively long) antennae, which was fun to observe.
Another lovely bug I saw was an early instar of the leafhopper assassin bug, Zelus renardii. I have seen both adults and nymphs of this species stalking the vegetation in our backyard. They are very colorful and seem to have quite good vision.
Bug Talk 