Velvet mite, Trombidiidae, from Iowa.
A pair of mating long-jawed orbweavers, Tetragnathidae, from Grand Teton National Park in Wyoming. Spiders have evolved a very unique method of reproduction; mature males inject sperm into small webs, then transfer them to special structures called palpal bulbs. They then use these turkey-baster-like appendages to transfer sperm to the female's abdomen.
Golden orb-weaver, Nephila clavipes, from Panama. These enormous spiders produce silk that is significantly stronger than steel while maintaining elasticity, making it a unique biopolymer that is currently being investigated for medical and military applications.