I'm hoping that someone can identify this bug/ caterpillar (?). I found it in the bowl of my toilet which is rather confusing as I'm on the first floor. When I lifted it out it reacted to my touch by starting to curl up so was alive. I would like to know what it would turn into as that would help me figure out how it got there.
Looks like a rat-tailed maggot, the aquatic larva of a drone-fly - one of the many hoverfly species. The "tail" is its telescopic breathing snorkel. The larva thrive in stagnant water - presumably it's been on a trip through the plumbing.