Advertisement Hey! I'm new to the site but have been reading material on here for a while. I live in Gainesville, Florida, and every time I go running down a certain road I see black spiders with a dark-red head on the sidewalk. they are probably about 1/2-3/4 inches long. I tried to take a picture of them last time but it ran into the grass, so it came out blurry. Does anyone know which spider they are? Thanks!