Tetragnatha elongata

Walckenaer, 1841

Elongate Stilt Spider

Tetragnatha elongata is a riparian spider in the Tetragnathidae, commonly known as the elongate stilt spider. It constructs small orb webs oriented horizontally or parallel to water surfaces near shorelines. When displaced onto water, it exhibits sophisticated orientation including concentric circling before traveling directly toward the nearest land. The is notable for its ability to walk on water using alternating leg movements while dragging its legs, and can employ silk extrusion to catch wind and be blown to shore.

Tetragnatha elongata by (c) Douglas Hooper, some rights reserved (CC BY), uploaded by Douglas Hooper. Used under a CC-BY license.Tetragnatha elongata by (c) Michael and Antoni Hinczewski, some rights reserved (CC BY), uploaded by Michael and Antoni Hinczewski. Used under a CC-BY license.Tetragnatha elongata by (c) Nick Chirico, some rights reserved (CC BY), uploaded by Nick Chirico. Used under a CC-BY license.

Pronunciation

How to pronounce Tetragnatha elongata: //ˌtɛtrəɡˈnæθə iːˈlɒŋɡətə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Long, slender body and legs characteristic of the Tetragnatha. Builds horizontal or near-horizontal orb webs, distinguishing it from most Araneidae orb weavers that construct vertical webs. Specific identification to level requires examination of genitalia, spacing, and relative jaw length to length.

Images

Habitat

Riparian adjacent to standing water and flowing fresh water. Constructs webs parallel to water surfaces.

Distribution

North and Central America, including the Caribbean (Cuba, Jamaica). GBIF records extend from Canada to Argentina.

Diet

Emerging aquatic insects including , gnats, and mayflies.

Behavior

web-building. When displaced onto water: performs orientation circles (10-20 cm diameter, 1-8 circles) before choosing direct path toward nearest shoreline; walks on water using alternating movements of first three leg pairs while dragging pair behind; can extrude silk to catch wind and be blown to shore (silking); travels approximately 10 times faster on water (38.9 cm/s) than on land (3.6 cm/s); adopts elongation posture (stick-like) when threatened to camouflage against vegetation.

Ecological Role

Important component of aquatic ; preys upon emerging aquatic insects, contributing to aquatic connectivity.

Similar Taxa

Sources and further reading