Black widow spider bites may cause sharp pain up the limb, but can also be painless. Two red fang marks, redness, tenderness, and a nodule at the bite site indicate a black widow spider bite.
Brown recluse spider bites are often painless at first. When the skin reddens, turns white, develops a red "bull's-eye" and blisters, it becomes painful.Andrej Shupilo ( Andrey)/PhotoSpin
Insect bites often result in redness and swelling. What mark do different bugs leave? Insects usually don't bite unless provoked, their protection against harm, but when you wake up to a mystery raised-red bump who is the culprit? Use this guide to decipher the bug bite code.