What is the period a beetle larvae(grub worm) is active before it transforms into a pupae?

Question

I'm doing a science project, where we are given grub worms to care for and observe everyday. So, I am wondering, how long is it till the eggs hatch to the point they turn into a pupae?

It is the June Beetle larvae.

Answer 1

Beetle larvae are often referred to as grubs, but there are several species of beetles. The period would depend on the beetle species. Some beetle larvae can take years to develop into adults. Check out this website, and see if you can make a closer match. If not, try searching beetle larvae images or larvae sizes, and see if you can figure out the species that way-- and then search the larva period using the species.

Check out...

http://en.wikipedia.org/wiki/Beetles

and

http://en.wikipedia.org/wiki/Scarabaeidae

Grub most often references the Scarab Beetles, but again, there are many species of scarab beetles. It is a good place to start, though.

Answer 2

It depends on the species of beetle. Since they are readily available from bait shops and are even occasionally household pests I'm guessing you have mealworms, which are the larvae of the Darkling beatle. The larva stage seems to be about 114 days (3 1/2 months), but how long you will have to wait of course depends upon how old the grub were when you got them. Keeping the eggs and pupae warm seems to speed up those portions of the life cycle. I don't know about the larva stage (but 25-30 degrees celcius is optimal for them)