Common stretch spider
Tetragnatha extensa
The common stretch spider is a frequent spider species primarily found near water bodies on reeds and grasses. Its body is extremely elongated and, when at rest, is pressed tightly against the substrate along with its legs, providing perfect camouflage as a stem. It weaves orb webs with an open hub, which often hang horizontally or diagonally over the water surface. The coloration is usually yellowish-brown with a dark folium pattern on the abdomen and a silvery underside.
Details
Identification
Extremely slender body, very long legs, silvery ventral side, characteristic resting position (longitudinal stretching).
Social behavior
Solitary, but often shows high population densities in suitable habitats.
Diet
Feeds on small flying insects, especially midges and mayflies.
Hunting strategy
Builds orb webs with an open hub in low vegetation over or near water.
Overwintering
Overwintering usually as a juvenile in vegetation or in the egg stage.
Ecology
Ecological role
Important predator in the ecotone between aquatic and terrestrial habitats.
Natural predators
Insectivorous birds, dragonflies, amphibians, and other spiders.
Competitor species
Other stretch spider species such as Tetragnatha montana.
Ecosystem service
Biological regulation of mosquito populations.
Threats
Loss of wetlands, intensive riparian management, and pesticide use.
Scientific profile
Profile
Distinguishing features
Characterized by a greatly elongated body and long legs. A key feature for distinguishing it from Tetragnatha montana is the light central spot on the sternum. The chelicerae are significantly enlarged and conspicuously toothed, especially in males.
Habitat
Prefers moist habitats such as the riparian zones of lakes and rivers, bogs, wet meadows, and reed beds. Widely distributed throughout the Holarctic.
Role in food web
Important regulator of insect populations in aquatic ecosystems; serves as food for birds, amphibians, and predatory insects.
Protection & threats
Main threats
Threatened primarily by the loss of wetlands, drainage measures, and intensive shoreline land use.
Population trend
Stable; the species is considered common and not threatened in Germany and large parts of Europe (Red List: Least Concern).