Yeah, potato leaf tomatoes are not combinations, they are just a tomato variety (though potatoes and tomatoes are all in the nightshade family). Plum lemon tomatoes are not a combination, they are just tomatoes.
Tomatoes are a favorite subject of hybridizers and there are about a million varieties of tomatoes these days, plus or minus five or six.
Scan through the images on this page:
except for one tomatillo picture that sneaked in there, they are all just varieties of tomatoes.