Tetragnathidae

Tetragnathidae, commonly known as long-jawed orb-weavers, is a family of spiders (order Araneae) comprising about 1,000 described species in roughly 50 genera. They are distributed worldwide, with the greatest species diversity in tropical regions, and many species occur near streams, ponds, and other moist habitats. The group is united by distinctive morphological traits and a characteristic web-building habit.

Members are characterized by elongated bodies and especially elongated chelicerae that project forward beyond the mouthparts, giving the group its common name. The eyes are typically arranged in two rows, and the legs are long and slender. The body shape and chelicerae are adaptations for their predatory lifestyle and web orientation.

Most tetragnathids construct orb webs, often long and horizontal or near-vertical, built among vegetation or across water bodies. Webs can be extended between reeds, shrubs, or grasses, and some species create webs at ground level or in rocky crevices. The capture spirals and supporting threads vary among species, and spiders commonly rest along the web axis with the front of the body facing the center.

Ecology and behavior: they prey on flying insects that contact the web, including moths and flies, and some near-water species harvest aquatic or semi-aquatic prey. Spiderlings disperse by ballooning. Reproduction involves males courting females, followed by sperm transfer and egg-laying; females typically guard silk egg sacs until hatching.

Notable genera include Tetragnatha (the type genus), Leucauge, Pachygnatha, and Metellina. Tetragnathidae represent a diverse group of largely harmless spiders that contribute to insect population control in a variety of habitats.