Common black spiders that enter houses include the mouse spider, black house spider and common house spider. The black widow is another common black spider with red markings, according to Termite.
Mouse spiders are large spiders that grow to up to 1 1/2 inches in length. They are black in color except for males, which can have red heads and fangs. The male will bite if provoked, which can be painful and cause severe illness. Medical attention should be sought if bitten.
Black house spiders are about 1/2 inch in body length and have a black, velvety texture. They spin a lacy web in places such as window frames, sheds and gutters. Their bites can cause nausea, pain, giddiness and headaches, but are not lethal.
The common house spider varies in color from dirty white to almost black, according to Spiderz Rule. They are up to 0.23 inches long and build large webs in the corners of rooms and under bedroom furniture.
The parson spider is another common house spider that may be black or brown in color. It is about 1/2 inch long. It hunts by walking around at night, concealing itself in nooks or clothing during the day. If disturbed, it may give a non-lethal but irritating bite.