A couple of days ago I noticed dozens of these little critters climbing up my utility room wall. I thought maybe the recent warm weather may have encouraged them in as I often leave the door open. I hoovered them up and thought nothing of it but this morning they seem to have quadrupled in numbers! I fear an invasion and have no idea what they are. I’ve hoovered, mopped and washed them away, took the dog for a walk and they are back!! What the heck are they? I have no idea where they are coming from. I’ve googled but can’t find anything which looks like them. Help!!