Toe hemorrhage after running

Hello all forum members!!
I have a riddle for you(and for me :) :
I noticed that when I run more than half marathon long runs, my 2nd toe tends to develop a hemorrhage under the toenail. This does not happen on shorter runs. I use the same shoes, which fit properly, are not new and do not have
any pressure points on my feet. I run on the same course. I am a veteran runner of more then a decade, but I usually run +/- 10 KMs. Recently I started running more and
noticed this strange phenomenon.
Does anyone have any idea why this is happening and how can I solve it?

Thanks!!
Dan