One thing you can say for insects, there is always something going on. Whether an insect undergoes complete or gradual metamorphosis, identifying a species can be tricky. Even simple metamorphosis still requires that an insect molts from one stage to the next, and sometimes the color change between molts is striking. Here is a quick look at some insects and the different appearances they may have.
This year I was able to raise a spined soldier bug, Podisus maculiventris, from an egg through to the adult. Although its body form was definitely that of a stink bug (Pentatomidae family), the color changes went from very colorful to a drab brown at the finish. Now I know all the instars, so in the future identifying this stink bug will be easy.
Caterpillars can also be hard to identify as they go through the larval stages. Most will have distinguishing forms or marks by the third instar, but sometimes the overall change may be more subtle until the penultimate instar is reached. Most identification aids show the final instar, even though a radical changes may occur throughout the larval stage. If possible, rear any caterpillars to the final instar to be certain of identification. Host plants may or may not be that helpful as some caterpillars can be found on many host plants. Others, like the double-toothed prominent, are found only on one host plant, in this case, elm. The cecropia, on the other hand, I have personally found on a variety of plants- from black cherry, alder, buckthorn and apple, just to name a few.
The orange-striped oakworms can be serious pests of oaks, especially in eastern Connecticut. Eggs are laid in large rafts near the bottom of many oak species and feeding results in severe defoliation. Note the black horns, though, which are present on caterpillars in all larval stages. The horns plus the host plant are valuable aids in identifying this pest.
Pamm Cooper All photos copyright 2016 Pamm Cooper