I say it is a wild plum (prunus Americana), there are lots of forms of them as they themselves have been widely cultivated. This is not even to mention those that have escaped cultivation. The color of yours is the approximate color and size of those I've seen in the woods here in Maryland. Another possibility is a wild seedling from a discarded seed. There are lots of possibilities here, but for practical purposes, it's a wild plum. The Navajo made red dye from their roots. At first I thought it was a gooseberry or currant. Looking more closely I recognized it as a wild plum. These will send up suckers under the tree that is said to make a fabulous rootstock for grafting.

I wonder...I have a plant of a similar size that I know for sure is a Nematanthus gregarius, but it looks very different than this one. Are there different cultivars? Or could my mystery plant be another Nematanthus species? The mystery plant's leaves are much, much longer than those of my "official" goldfish plant. They are also a much lighter green. The official goldfish plant already has its telltale orange buds, too, whereas the mystery plant has no sign of anything but leaves at this point. I guess I can try moving it to more sun and see if its growth changes any. It's actually a lot more compact at the top, since I brought it home from the nursery.

It's a juniper. Very likely a seedling of eastern red cedar, Juniperus virginiana, a native to much of the eastern half of the country, including Texas. There is also another native juniper that could be a potential candidate, Juniperus ashei. Both are considered weed trees, as they self-seed everywhere.

Thanks for your replies and suggestions. I will take a sample and visit my local extension service office. That was really great advice. :) However, I wish those "3 tiny holes" were the extent of the damage This leaf is actually in very good shape. There are no aphids that I can see and I have not been able to find any other bugs on the plant. I will visit my local extension office where I can find some help and not criticism.. Perhaps I am wrong about these bugs causing the damage, but there is no doubt lots of damage to my tomato plant. I had holes inside some of my small fruit, even after this posting.. I opened one of the fruit and found nothing living inside.