Black Ants at Home

hi everyone

In the end of last summer, when I was in my village. one day went to my field area with my grandfather. there was a tree. and there was many holes of ants(homes of ant). I got this picture from there. rain season had start. so, ants was coming outside of homes.
 most important thing is that they are not poisonous ants. they have very sharp and strong teeth. this is totally black it has a white line on back.