Biology, Natural History, and Ecology of Embioptera - Webspinner

Embioptera

Webspinner

Blythe Lang
Ecology Major
University of Georgia, Athens

Overview
Families
Phylogeny

Geographic distribution
Natural history
Links to other sites
Acknowledgements

Embioptera

photo copyright Gordon Ramel

Discover Life | All Living Things | IDnature guides | Insecta | Embioptera

Overview

"Webspinners are small, usually from 4 to 7 mm in length. Males may or may not have wings, but females never have wings. They live in colonies in silk-lined galleries in soil or leaf litter and among mosses and lichens. They feed mainly on dead plant matter. Silk is spun from glands in the forelegs; these glands make the webspinner look like it is wearing boxing gloves. These insects can run quickly in either direction -- either head first or tail first. They sometimes play dead when they are disturbed. They are not common and are found chiefly in southern states like Texas."-- (Texas Virtual Collaborative's Middle School Science Curriculum Site)

Anisembiidae
Oligotomidae
Teratembiidae

Taxonomic Category Scientific Name Common Name
Phylum Arthropoda Arthropods
Class Insecta Insects
Order Embioptera Webspinners

"The name Embioptera, derived from the Greek "embio" meaning lively and "ptera" meaning wings refers to the fluttery movement of wings that was observed in the first male Embioptera described. "-- (N.C. State University Entomology Dept.)

Geographic distribution

Uncommon - found in silken nests under bark or leaves in tropical and subtropical climates.

North America Worldwide

Number of Families 3 8

Number of Species 9 ~200

N.C. State Entomology Dept. site.

Natural history

"The order Embioptera (webspinners or embiids) is another group within the Orthopteroid complex that probably appeared early in the Carboniferous period. Many insect taxonomists believe webspinners represent another evolutionary "dead end" that diverged about the same time as Plecoptera. Determining phylogenetic relationships for this group is unusually difficult because the Embioptera have a number of adaptations not found in any other insects. The tarsi of the front legs, for example, are enlarged and contain glands that produce silk. No other group of insects, fossil or modern, have silk-producing glands in the legs. The silk is used to construct elaborate nests and tunnels under leaves or bark. Webspinners live gregariously within these silken nests, feeding on grass, dead leaves, moss, lichens, or bark. Nymphs and adults are similar in appearance. Embiids rarely leave their silken tunnels; a colony grows by expanding its tunnel system to new food resources. Well-developed muscles in the hind legs allow these insects to run backward through their tunnels as easily as they run forward. Only adult males have wings. Front and hind wings are similar in shape and unusually flexible; they fold over the head when the insect runs backward through its tunnels. Blood (hemolymph) is pumped into anterior veins to stiffen the wings during flight. In Embioptera, the mouthparts are directed forward (prognathous) rather than downward as in other primitive orthropteroids. This may simply be an adaptation for life in a tunnel, or as some taxonomists have suggested, it may mean that Embioptera are really more closely related to earwigs (order Demaptera). Most Embioptera are tropical or subtropical."-- (

N.C. State University Entomology Dept.

Links to other sites

For more information concerning webspinners see N.C. State's Entomological site.

Acknowledgements

Thanks to Sabina Gupta, Denise Lim, and Dr. John Pickering for technical and web support in developing this page.

Discover Life | All Living Things | IDnature guides | Insecta | Embioptera