Family

Linyphiidae

Linyphiidae is the second-largest spider family in the world and by far the most abundant in temperate North America by individual count, yet it is almost entirely overlooked because most members are under three millimetres. They build horizontal sheet or bowl webs and hang upside down beneath them.

Diagnostic characters

  • Very small size, most under 3 mm
  • Hangs upside down beneath a horizontal sheet
  • Bowl-and-doily weaver Frontinella pyramitela builds a distinctive two-layer structure
  • Males of many genera have bizarre carapace turrets and lobes bearing the eyes
  • Enormous densities visible as dew-covered sheets across lawns and fields

Habitat and seasonality

Grassland, leaf litter, crop canopies, moss, shrubs, and soil surface. Occasional accidental indoor occurrence only.

Active year-round including winter; many species are cold-tolerant and mature in autumn or early spring.

Medical significance

None. Body size precludes any meaningful bite.

Ballooning and dispersal

Linyphiids are the dominant ballooning spiders in temperate regions. Individuals climb to an exposed point, release silk into rising air, and become airborne, sometimes travelling hundreds of kilometres. This is the mechanism behind mass dispersal events in which fields become blanketed in gossamer overnight, and behind the family's rapid recolonization of disturbed agricultural land.

Agricultural importance

Because of their density and their ability to recolonize quickly after tillage or harvest, linyphiids are among the most important arthropod predators in cereal systems. European and North American field studies document significant aphid suppression by linyphiid assemblages in spring, before larger predators become active.

Families most often confused with Linyphiidae

FamilyHow to separate it
TheridiidaeCobweb weavers build an irregular tangle with gumfooted lines rather than a defined sheet
AgelenidaeFunnel weavers sit on top of the sheet at a funnel retreat, not beneath it

References

  1. [1]World Spider Catalog, version 26 - Natural History Museum Bern. Accessed 2026-06-14.
  2. [2]Spiders of North America: An Identification Manual, 2nd ed. - American Arachnological Society. Accessed 2026-06-14.
  3. [3]Common Spiders of North America - University of California Press. Accessed 2026-06-14.