Weird Splodgy Grey Fast Thing in Millipede Tank

[7Fin]

I actually don't know. I saw it scamper somewhere yesterday, and today I saw it resting on a leaf. I tried to get a pic but the Weird Splodgy Grey Fast Thing (WSGFT for short) got away. No idea where it came from. For a clearer description, said WSGFT has small, round, pebble like body. Its shell looks rubbery. I has two long wire-like feeler things moving around on its butt, and it's legs are average. The WSGFT might not be predatory, but it is extremely fast and relatively intelligent. It's almost like a rubbery silverfish-oversized springtail-beetle.

Any idea what the WSGFT actually IS? Is it a threat to my pedes? I'm especially worried because my rainbow is molting as we speak.

 

[mickiem]

I would be afraid of it; but that's me! If it didn't receive an engraved invitation it isn't allowed with my pedes.

 

[Charlie69]

Something like this?

 

[MetalMan2004]

Something like this?

Haha if OP thinks isopods are fast and intelligent then they would be quite surprised by the quickness and agility of a tarantula.

 

[LawnShrimp]

There aren't too many things that can hurt a millipede. If it is an isopod, only one can't do damage.

 

[mickiem]

What about an earwig? They aren't gray, but in a blur could appear gray. Hope you can get a photo!

 

[7Fin]

It's surely now an earwig, I got a good look at the colours, there is no protruding head, and the probe things on its butt are much more long and wirey. It's certainly not an isopod. Too fast, and the probe things are again, too long. It's shell almost looked translucent. The closest thing I can find to looking like it is a silverfish, and even then it certainly isn't one of those. Might be some sort of... Giant springtail? Or maybe some sort of weevil? Whatever it is I'll try and take it out and get a picture when I find it. I don't want it in my pede enclosure, especially since I don't know what it is.
Weird.

 

[dragonfire1577]

Is it a bristletail? like this

 

[LawnShrimp]

Is it a bristletail? like this View attachment 258915

That's what I thought too at first but the WSGFT was described as "round", not long.

 

[7Fin]

What @LawnShrimp said. A bit more rubbery pebble like, and the shell looked less segmented.