Butterworms, or Trevo Worms as they are commonly known in their native Chile, are the larvae of the Chilean moth. Butterworms are indigenous to Chile and feed primarily on the Trevo Bush (Trevoa trinervis). As you may have suspected, the name "Trevo Worm" has been derived from their eating habits. Trevo worms were likely renamed to Butterworms as a result of their colour and scent. Butterworms have a natural fruity/buttery scent and a reddish - yellow colouration.
The term "Butterworm" is also easier to market than the common "Trevo Worm".
Butterworms are imported from Chile regularly and are under strict import regulations. As a result of the potential infestation of the Chilean moth, which is considered a pest anywhere besides their native Chile, the Butterworms being imported are hit with low level radiation to prevent them from pupating and breeding.
Butterworms are fairly expensive to purchase compared to the more common feeder insects, like Crickets, Mealworms, Superworms, and Waxworms. Their cost is to help offset the costs associated with their importation, since breeding butterworms locally isn't possible.
 Nutritional Information
Calcium (ml/100 grs) 42.90
 Food & Water
Butterworms eat the leaves of the Trevo Bush naturally, but do not need to be fed anything in captivity. Once refrigerated, explained below, they will fall into a hibernative state and their metabolism will slow down drastically. As a result, neither food or water needs to be offered to these insects.
It is crucial to keep these insects dry. Moisture will lead to mold and can destroy the Butterworms in the container.
Most online retailers will ship their Butterworms in small plastic cups. These cups will contain a typical substrate - medium of wheat bran or alternate substrate. The substrate is not a food source, but is designed to help absorb moisture from the container. Once received, you do not need to change their housing, unless you have spotted mold forming.
To get the longest lifespan out of the Butterworms you have purchased, you will want to refrigerate them. Refrigeration at temperatures between 42-45 degrees F will place the worm into its hibernative state. This state of hibernation will allow the Butterworms to remain unfed and unwatered for several months with minimal loss.
Breeding Butterworms is a near impossible feat in the United States. The Butterworm, which is the larvae of the Chilean moth, is irradiated before being exported from Chile. This irradiation is to kill off bacteria and to sterilize the Butterworms from pupating into their moth form. In order for breeding to occur, you need the moths. As you can see, without them having the capacity to pupate, breeding is not possible.
These insects are considered a pest, which is why breeding is not favored outside of Chile. Strict import laws regulate the flow of these insects to assure that breeding moths are not introduced, accidentally, outside of Chile.