Thank you all for the comments. Here's another picture from a different angle.

Thanks Carolus! Yes, c. schwartzi is the closest match I have been able to find. However, as you have also observed, these specimens seem significantly darker.

I was wondering if anyone could please help me in identifying my new cory. I just picked up three of them at my local shop and the only info I have to go on is that the owner thinks they are from Peru. Thanks!