Larva to Pupa
When raising a caterpillar, how can you tell that your caterpillar no longer wants to feed and wants to make a chrysalis? After having raised several species of butterflies pertaining to most butterfly families, I have started to notice patterns applicable to butterfly families, genera or species groups.
This section will help you learn how certain groups of butterflies provide some visual evidence that they want to pupate. These evidences can be categorized as follows:
- The larva changes color
- The larva purges it undigested food
- The larva crawls off the plant
- The larva silks itself to the top of a container and hangs as a 'J'
- The larva silks itself profusely inside a rolled leaf nest
Some last instar caterpillars will change color as a cue that it has finished eating (or soon will finish eating) and seek a spot to either diapause or form a chrysalis. Sometimes this color change goes from the background color of their host plant (green) to a a more earthtone shade (brown) similar to the likely background color of where they will diapause or pupate.
Please note that most of these thumbnails do little to illustrate these differences. Please click on any image to start slide show to see the full images.
Termed a prepupa, most mature fifth instar larvae that belong to the superfamily Nymphaloidea will silk themselves underneath a leaf or twig and form a cremaster from which the larva will then attach itself to form a 'J' before pupating.
Swallowtails purge their undigested food before wandering in search of a suitable place to pupate. Although a mess to cleanup, seeing purges tell you that you no longer need to feed your swallowtail caterpillar.