That first web site is the most accurate picture I've seen yet. Unfortuneately for me, I bought the last ones the LFS had. I guess I'm going to buy a few other types and see how they act with each other.Maybe they are C. melanistius melanistius?
http://www.aquarticles.com/articles/breeding/Bryson_Corydoras melanistius melanistius.html
Or maybe C. Punctatus Punctatus?
http://www.planetcatfish.com/catelog/species.php?species_id=69