Insect and Spider Identification: Unsure what this spider is!!, 1 by SGMountainGuide

SGMountainGuide wrote:
I was hiking in Southern California today down a dry riverbed in the Santa Ynez Canyon. I came across two separate webs within 50 feet of each other both with this exact same spider in it. Based on some comparisons to pictures I found on the internet I think it might be a Zygiella x-notata, however there are some things that are NOT common between the two such as body shape/color. Please help me identify the spider in the picture I have attached, and help me gain any knowledge on it, as I do a lot of hiking in this area - bite? Poisonous? etc... Thanks!!