Family Tetragnathidae - Long-Jawed Orb Weavers

	Family Tetragnathidae - Long-Jawed Orb Weavers Recently separated from family Aranidae, the tetragnathids spin less elaborate webs than their larger sisters. Live spiders photographed in the wild at various North American locations. Spider Index \| Spider Main \| Funnel Web \| Orb Web \| Nursery Web \| Cobweb \| Insects

Tetragnatha elongata

Larger spiders in this family are often found near water, especially moving water of rivers and streams. They build orb webs in the horizontal plane, often just inches above the surface of water where they can catch emerging insects like midges, mayflies, and stoneflies. I have seen them construct elaborate scaffolding atop plants at the water's edge, upon which they can travel quite rapidly, seemingly on thin air.

Smaller species build webs in fields and meadows, often in trees and shrubs or low foliage in the forest understory. Most of their orb webs are built closer to the horizontal than vertical, with a large open area in the center through which the spider can pass to access both side of the web. Other species are active hunters and build only the aforementioned scaffolding.

Tetragnatha straminea

Nephila clavipes

Venusta Orchard Spider

Tetragnathid spiders are usually easy to identify by their eponymous huge, powerful chelicerae (jaws) and long, slender abdomen. Like the other family of orb weavers, the Araneidae, these spiders have eight eyes and 3 claws on each tarsus. There are about 25 species in North America [1].

The Venusta Orchard spider, a very common woodland arachnid, is a member of this family. The Venusta (after Venus, the goddess of beauty) spider is nearly ubiquitous in the forest understory here in northern Illinois where they sit upside down in their smallish (6-8 inches or so) horizontal orb webs. Their chelicerae are not nearly so prominent as other spiders in this family.

Tetragnatha laboriosa

References

Paul Hillyard, Private Life of Spiders (New Holland Publishers Ltd, 2007)

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Class Arachnida / Order Araneae: Spiders are the largest group of arachnids. They are easily recognized by their eight legs, and there are few creatures great or small that elicit such irrational fear in mankind. The vast majority of spiders are completely harmless and offer beneficial services, chief of which is keeping the burgeoning insect population in check. I am continually amazed at the resourcefulness of these supremely successful predators.
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