There are nearly 1,000 species of spiders found in Texas, but only a few are harmful to humans.  Most are beneficial, feeding on pests of agricultural crops ants and mosquitoes that they ensnare in their silken traps. 

Only two groups of spicers are considered poisonous to humans.  They are recluse spiders and widow spiders.   Tarantulas, jumping spiders, wolf spiders and some other spiders are hairy and formidable-looking, but their bite is typically less harmful than a bee sting.

While many of us have a spider phobia, most spiders are really harmless. 

http://www.spiderzrule.com/commonspidersusa.htm is a useful spider link.