Can anyone id this caterpillar / larvae in my substrate?

[Andrew Ferguson]

I noticed a small but shiny round thing peeking out of the substrate. As I moved the tank it seemed to retract into a small tunnel. I dug it out and found a small caterpillar like larvae (bulbous head, hairs and legs just like a caterpillar). I have a few questions basically, is it harmful (in case there are more) and secondly, what is it?



It measures about 10-13mm and is translucent.

Thanks in advance.

[Nick L]

The larva certainly looks lepidopterous (i.e. a caterpillar of a moth). To be sure check to see if there are a pair of legs at the very end (there are normally 3 pairs of ‘true’ legs behind the head, a gap, then 4 pairs of ‘pro’ legs, then another gap, and finally a pair of ‘clasper’ legs at the very end). If there are no legs at the end it is likely to be a beetle larva. If you have plants in with your T it could be anything! If you don’t I’d suggest, given the size, that it is the Brown House-moth (Hofmannophila pseudospretella) – this is a fairly ubiquitous and common species whose larvae feed on a wide range of dead animal and plant material. There may be a few more in there but I’d doubt it; just whip ‘em out if you see any more; they are not doing any harm but then again not doing much good either! If you want to rear the larva through to a moth just put it in a film-canister/pot with say a dried-out dead cricket and maybe some wool/cotton or feathers. It will probably pupate fairly soon given it’s size and a moth will emerge 2-3 weeks later – if you post/email a photo I will be able to ID it for you.