Identifying unmarked pill?

Masso certainly seems to have located the only thing that this pill "could" be: metoprolol tartrate - 25 mg. I have NEVER seen any pharmaceutical marked so mysteriously as this; there's always a letter and number on it and an indication on the bottle label of what the markings are so that you can be sure the markings on the pills inside correspond.

This would scare the **** out of me. First, metoprolol is similar but not the same as atenolol. Second, it's apparently for only 25mg, not 50mg. And third I personally have never heard of this pharmaceutical company in my two decades of using atenolol and other generics. When you see on the website the pharmaceutical company name followed by "USA" that usually means the address on the site is probably just an import office and the pill could come from anywhere - New Guinea, Afghanistan, Mongolia... Usually, the location of the production factory is indicated in the website, but I can't find one on their site (maybe I missed it).

I would show this to my doctor and have him/her contact the pharmacist and ask for a better-known generic ATENOLOL 50mg. I have taken Zydus, Teva, and Aurobindo - Zydus seems to work the best for me, but the others are quite popular. My pharmacist keeps a record of my preferred generic of each medication I take, because even some well-known generics of certain drugs may have bad side effects - the various generics of one drug are not the same. They can have very different excipients, inactive ingredients that bind the pill together, and artificial colors (some of which I'm very allergic to). If your pharmacist will not order another more standardly marked, better-known generic for you, I would definitely change pharmacies if I were you.

Could this be your pill?: https://www.drugs.com/imprints/1-6964.html

Atenolol pill images: https://www.drugs.com/imprints.php?drugname=Atenolol