I am raising a Thai strain of silkworms. This spring, I had one good-sized group, and they all made moderately sized cocoons – except for one, which turned out tiny. The summer group, I will admit, got a little bit neglected; I moved during the middle of their cycle, and so they sometimes got not enough food, or old leaves because I couldn’t find the new ones near my new house… you get the idea. Poor little red-headed step-child worms.
So – some of them decided that life was tough, and they would cocoon early. They spun up in the fourth instar, making TINY but perfectly-shaped cocoons. My friend Eika explained that these are called trimoulters, and they are typically caused by feeding over-matured leaves.
Now – these are a naturally small strain. Chihuahua puppies are never going to grow up to be German shepherds – but the trimoulters are *freakishly* small. Here’s a comparison of normal Thai cocoons, hybrid Chinese cocoons, and the trimoulters.
and here’s a comparison of the normal (smallish) Thai pupa, and the trimoulter pupa
And, in a move that should surprise no-one, they hatch out as freakishly small moths. They’re SO CUTE. Like pinchums-widdle-cheekses cute.
Despite being tiny, they are breeding vigorously. I’m curious to see what will come of it – and whether the eggs will be visible.