I made a goof: The green midge Spider (Micrommato virescent), he showed up one day after I added more hyacinth plants. Also more swamp pond water was added every few days to replace all that was lost from the hyacinths and natural reasons.
Now since my caterpillars had begun the process of forming pupae cases, I figured I better find out what species they were. From my local library, I borrowed books on insects and butterflies. In the Audubon Society Field Guide To North American Insects, I discovered my caterpillars. They were from the Acraea Moth (Estigmene acraea), described as a caterpillar 2 1/2" long (65mm), black body covered with dense, long rusty-red hair. Their habitat was in fields and pastures, and marshes. They range throughout North America, except not in northern Canada. Their food is herbaceous plants and cord grasses in salt marshes. Nickname: "Salt Water Caterpillar."
My aquarium had become a nursery. The water beetles and snails were consuming the roots of the frog-bit plants and large clusters of be-be sized white eggs are attached to the roots of the water hyacinth plants. The fact that the caterpillars changed their eating habits once in the aquarium, made me wonder if all vegetation eating caterpillars would ajust their diet if put in this type of situation??
Something to test another time.
It is now the end of December 1992, and this morning I had a very discouraging find. The temperture changes during the night with our furance running caused the tank to become warmer than it should have been. Over night some leaves on the hyacinth plants turned moldy, and the mold formed a light white dust powder on the water hyacinth where the last two caterpillars were eating.
I can only conclude that the caterpillars must have eaten some of the mold powder which in turn killed them. Their hair fell out and their bodies turned whitish over night. I guess the lack of movement of the water caused slight stagmentation and so the mold formed.
All the other creatures and insects in the aquarium remained healthy. I clipped off the moldy leaves and removed the dead caterpillars from the tank.
The several caterpillar pupae cases, now at the top of the aquarium were fine and I was set to wait for the moths to emerge.
