This tiny black bug is a White-Margined Burrowing Bug (Sehirus cinctus). That is a very large name for such a small bug. They measure up to 1/4 of an inch, and are glossy black, although some specimens may be dark reddish-brown, with a distinctive white border around the body. This is the only species within this genus in North America. Although there are a few sub-species recognized. These are very common bugs found throughout Canada and the United States. Look for them in woodlands, gardens, and yards. They are frequently found on weedy plants like henbit, and dead-nettle. In my own garden I find them on a wide variety of plants, but they seem especially fond of Lambs Ear. They feed on the seeds of plants in the mint family. The adults will overwinter in leaf-litter on the ground and become active again when spring returns. After mating, the female will lay her eggs in a shallow depression that she will provision with the seeds from various plants in the mint family. The females exhibit nurturing and protective tendencies towards the larvae in the early developmental stages. Once the larvae have reached the 3rd molt, this maternal care deminishes. Keep in mind the small size of these bugs when searching for them, close examination of plants within the mint family will surely prove fruitful and you will most likely see numerous individuals.