Mountain stretch spider
Tetragnatha montana
The mountain stretch spider is a widespread orb-weaver that prefers habitats close to water and damp forests. It possesses a characteristic elongated body and extremely long legs, which it extends parallel to the surface when in a resting position. Its webs are usually stretched horizontally or at an angle within riparian vegetation. The species is an important component of the ecosystem in transition zones between water and land.
Details
Identification
Elongated abdomen; underside of the prosoma (sternum) uniformly dark without a light median stripe; characteristic dentition of the chelicerae in males.
Social behavior
Solitary; exhibits specific courtship rituals during the mating season.
Diet
Feeds on small flying insects such as midges, mayflies, and caddisflies.
Hunting strategy
Construction of orb webs with an open hub in the vegetation; ambush predator that detects vibrations in the web.
Overwintering
Overwinters as subadults in leaf litter, grass tussocks, or under loose tree bark.
Ecology
Ecological role
Important predator in aquatic-terrestrial ecotones, regulating insect populations.
Natural predators
Insectivorous birds, other spider species, parasitic wasps, and amphibians.
Competitor species
Other species of the genus Tetragnatha (e.g., Tetragnatha extensa) and swamp orb-weavers.
Ecosystem service
Natural pest control by consuming large quantities of midges and other insects.
Threats
Loss of wetlands, channelization of rivers, and destruction of riparian vegetation.
Scientific profile
Profile
Distinguishing features
Characterized by an extremely elongated body and very long legs. Unlike the very similar T. extensa, T. montana lacks the light longitudinal stripe on the sternum. Males possess conspicuously long, forward-pointing chelicerae with specific dentition that plays a role during mating.
Habitat
Prefers moist habitats such as forest edges, hedges, bushes, and riparian vegetation. Compared to T. extensa, it is less strictly tied to the immediate vicinity of water and more frequently found in the shrub layer of forests.
Role in food web
Important predator of small insects in ecotones (transition zones); serves as food for birds, lizards, and predatory insects.
Protection & threats
Main threats
Loss of structurally rich forest edges and wetlands due to intensive agriculture or forestry monocultures; drainage measures in floodplains.
Population trend
Stable; the species is widespread in Central Europe and commonly found in suitable habitats.