Spiders in the family Dictynidae are small, sedentary (that is, they build a web and stay in one place) arachnids that build irregular mesh webs to snare prey, and as shelters for themselves. The spider begins by spinning a simple framework of parallel rows, then overlapping those with another set at right angles. The whole web is infused with sticky ribbons consisting of dry support lines and a woof of curled threads the spider pulls from the cribellum by means of a comb of bristles, called a calamistrum, on its fourth metatarsus. [2]

Being quite gregarious spiders in habit, these webs can become a serious problem when spiders congregate in large colonies - they are known to completely blanket small trees or shrubs. In the American Southwest, these communal webs can cover the walls of buildings!

Not much is known of the life cycle of these tiny spiders, but it is thought most species live only a single year. The females produce a few eggs at a time, encasing them in small egg sacs suspended in the mesh web.

Soldier fly entangled in mesh web

Family Dictynidae: "Small cribellate spiders of the suborder Araneomorphae with one pair of book lungs and a single transverse tracheal spiracle immediately in front of the spinnerets. Cribellum undivided except in a few species of Mallos. Calamistrum always uniseriate and runing nearly the full length of the laterally compressed fourth metatarsus. Chelicerae robust, free at the base, with a conspicuous lateral condyle sometimes developed to a horn, and with both margins of the furrow toothed. Legs of moderate length, only rarely with well-developed spines, and with three tarsal claws. Trichobothria present on metatarsi and tarsi except in Dictyna and some Mallos. Anal tubercle of moderate size, short, lacking a conspicuous fringe of hair. Eyes typically eight in two essentially straight rows, but the anterior median sometimes reduced in size or completely missing. Male palpus always lacking a median apophysis on the bulb." [2]

Spider has injected the fly with its paralyzing venom, which also serves to digest the fly's insides so the predator can vacuum the slurry.