Description of "Thrips" (word used for both singular and plural.)
There are about 5000 described species of thrips (insects Order Thysanoptera). Most feed on fungi and live in leaf litter or on dead wood.
The species that feed on higher plants occur mostly in the Family Thripidae. This family includes the important pest species. Some
reproduce in flowers and feed on the cells of the flower tissues, on pollen grains and on small developing fruits. Many of the
flower-living species are facultative predators. Other species primarily feed on leaves. Some species are obligate predators
on small insects and other arthropods. Some of the most common pest species feed on a wide range of plants and even prey on mites.

Adults emerge milky-white, but soon turn brown and begin feeding. The female is approximately 1.65 mm (.065")long and slightly
larger than the male. The antennae are dark brown except for the 3rd segment which is light brown. The wings have a light
tranverse band near the base. The egg is about 0.3 mm (.011")long, opaque white, smooth, and bean-shaped. Eggs are deposited in
the leave tissue and corms. The two larval stages are light yellow and are usually found beneath the leaves or bracts.
The fully developed second instar larva is about the size of the adult. The first pupal stage is distinguished from the
second pupal stage by having forward projecting antennae and short wing pads. The 2nd pupal stage, which is a quiescent
period, has the antennae folded over the back and much longer wing pads.

Lots if info on the web but here are two sources:
http://thrips.ifas.ufl.edu/thripsweb/thripsbiology.htm
http://en.wikipedia.org/wiki/Thrips