Lump under cat throat ~ is it because he's thin? Is this part of the cat skeletal system?

Hey. So I've noticed this before but have chosen late at night after drinking too much tea to start worrying about this. My male cat is quite thin. He has FIV and this may be why he never really puts on lots of fat. Beneath the soft part of his throat, on the front of his body, and by beneath I mean lower towards the floor, there is a bone/hard part of his body that kind of protrudes. I have looked at diagrams of cat skeletal system and it may just be the clavical? This diagram shows it the best. Most show cats from the side so I can't tell.

It may be that because he doesn't have a great deal of muscle mass or fat that it feels a little odd to me. I've had cats all my life and never noticed it, but they were all muscular and healthy. He has been examined by a vet for other things a few times and no one mentioned it. Sorry. Just have these little panics. He doesn't seem bothered when I touch it. I can have a vet see him again, but in the meantime does anyone have any thoughts?

If your really concerned you should def consult a vet but I assume it's just the breastbone. I had the same concern when I noticed the same thing on my CKD cat. One day I noticed it really protruding and had it checked out by my vet who thought I was crazy. She said it's just more prominent since he's lost weight.

Haha! Yes, I am fairly sure it is just his breast bone and I became fixated on it. I will have someone check it out soon, but he really is not bothered at all. I think he does lack muscle around that area. Thank you for your comment - it does reassure me to read it and I will def take your advice to just be sure.