Devils at Rest

The Hickory Horned Devils (Citheronia regalis) have finally shuffled off to pupation and hopefully we will be seeing some adult moths in the spring and summer of 2015!























This photograph shows, from left to right:
1.) a late instar Hickory Horned Devil caterpillar
2.) a caterpillar which is shrunken down and preparing for pupation
3.) a light brown fresh pupa
4.) a dark colored pupa which is the final appearance for this species during the process of metamorphosis.

What about a cocoon?

Rather than making a cocoon, as so many moths do, this species overwinters in their unadorned pupa. As late stage caterpillars begin their work of getting rid of extra fluids and shrinking down, they will seek out a location in leaf litter or loose soil and begin to burrow in. By burying themselves in soil and leaves, the pupa receives not only camouflage but also a protective and insulating layer that will help to protect the developing moth from cold temperatures.

What happens in the pupa stays in the pupa.

During the coldest part of the year, the pupa will enter a stage called diapause. A pupa entering diapause will cease development and the metamorphosis of the insect inside will halt until conditions become more favorable to the survival of the insect. The only energy used upkeeps the integrity of cells from breaking down, but does not cause cells to change, reproduce, or grow. A caterpillar in diapause will cease eating, growing, shedding or burning food-fuel that has been stored. They basically just stop. Diapause is a true suspended animation.

One the weather warms up and improves, metamorphosis picks right back up where it left off and the moth continues to develop inside the pupa. Here at MOSI, we overwinter our Hickory Horned Devil pupa in a bin of loose soil that we moisten from time to time.

Springtime for Devils

The adult of the Hickory Horned Devils is commonly known as a Regal Moth. The moths will emerge from their pupa right around dusk, climbing out of the pupa and then free of the dirt and leaves that once protected them from cold and hid them from predators. Once free, the moth will spend some time allowing theirs wings to expand and harden. When that is complete, the adult moths immediately begin seeking out mates. Females will start laying eggs as early as the next night.

Regal Moths can be seen flying from as early as May to as late as September. 

It begins all over again!

Thanks to MOSI Outside friend, Kristen J., we have just been gifted with another small clutch of Citheronia regalis eggs! These eggs have just started to hatch and the first few caterpillars have begun dining upon the leaves of Sweetgum. Over the next few months, you'll likely be hearing and seeing more about this species.

If you would like to read more about our experience rearing this species as MOSI Outside, follow this link to see the rest of our posts about our time with the Devils.