Brown recluse spiders have much smaller bodies than most wolf spiders, and their legs are a bit thinner, too. The abdomen of a brown recluse is uniform brown, without markings, and there is a characteristic violin-shaped dark patch on the thorax. read more
If you don't quite know what you are looking for, lots of things look like brown recluse spiders. Here is a site where you can learn to separate the recluses from the socialites;-) lineups Actually, hardly any spiders genera do not have some capacity to produce and inject venom, but I know what you mean. read more