These ants have been showing up in my room, crawling up my bed at night and sting/biting me repeatedly. The sting is not very painful (class I) but itches like crazy for days and I can’t get a good night of sleep in a week. I think they are clearly nested inside the room and I will have to get rid of them fast. But I am also interested in identifying the species and learning more about them because I never saw this species around before. In fact, until I got a good look at the head/antennae I considered they could be some other insect.
Northern Portugal. Urban environment.
SECOND-Habitat of collection.
Bedroom. They show up a lot on some cardboard boxes but could be in wood.
THIRD-Coloration, hue and pattern?
The head and abdomen dark brown. The abdomen is shiny. The thorax is lighter brown. It resembles a bit the heart shape of Crematogaster but not as perfect as C. scutelaris. Much more elongated rather.
Most of them are clear in the pictures. I am almost sure they sting me not bite me. I could not get a picture of the sting out though. They smell a lot like formic acid to me too.
FIFTH-Length in millimeters. (Width is also helpful.)
I could find a good ruler at the moment, only this one for now.
SIXTH-Anything else distinctive, such as odor, behavior, etc.
They are calm and walk slowly. I find them isolated and they wander alone not in lines.
I’ve been using several keys to identify the species with no success. Does anyone recognize these guys?
P.S.: I have a video of the head where the mandible's chweing motion is visible if it is helpful.