I found some aquatic larvae in a tree hole on March 23. An entomologist at WSU had never seen them before, but with books and microscope identified them as aquatic syrphids, and suggested I try to hatch them out. I have kept them in an open container with the detritus from the tree hole since then, replenishing the foodstuffs as necessary. I started with 4, and when I left town several days ago was aware of one remaining in the larval form, and was not sure whether the others were dead or whether there were hidden pupae. When I came back home two days ago, I found one live larvae and, in the sink next to the container, one dead syrphid fly. I am very sad that it died. I really didn't expect anything to hatch while I was gone, since I hadn't seen any pupae! I sent photos to the entomologist and he thinks it is Chrysotoxum. I would like to know more.