Dispatch From the Butterfly Ranch

Egg, larva, pupa, adult - the four basic life stages in an insect’s life cycle.  I’ll be visiting these four stages this season on the Butterfly Ranch mostly as it relates to monarch butterflies but not necessarily restricted to them. The last time I visited this subject was June 12th when I first began finding monarch eggs laid on the milkweed host plant. 

Stage two refers to a butterfly or moth at the caterpillar or larva stage.  Both terms are correct – but most biologists use the term larva. This is the stage that a monarch butterfly does all of its growing.       

As the caterpillar feeds and grows in size it has to molt – or shed - its skin.  The shed skin is eaten before the caterpillar resumes dining-upon milkweed with the period of time between molts referred-to as instars.  With normal summer temperatures the entire larval stage of monarchs lasts from nine to fourteen days with the caterpillar growing through a total of five instars before they reach the third stage of life.     

This larva is in the fifth instar and I think it is beginning to look for a place to hang and commence stage three.  

click on image for a closer look