Agelenopsis

American grass spiders
File:Pennsylvania Grass Spider.jpg
A. pennsylvanica female in web
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Agelenidae
Genus:	Agelenopsis Giebel, 1869
Species
See text.
Diversity
13 species

Agelenopsis is a genus of spiders, known as American grass spiders. They weave sheet webs that have a funnel shelter on one edge. The web is not sticky, but these spiders make up for that shortcoming by running very rapidly. The larger specimens (depending on species) can get up to approximately 19 mm in body length. They may be recognized by the arrangement of their eight eyes into three rows. The top row has two eyes, the middle row has four eyes, and the bottom row has two eyes (spaced wider than the ones on the top row). They also have two prominent hind spinnerets, and somewhat indistinct bands on their legs. They also have two dark bands running down either side of the cephalothorax.

Agelenopsis aperta, the American funnel-web spider, produces agatoxins. Their bite causes rapid paralysis in insect prey, though their venom is not medically significant to humans.

Name

The genus name is a combination of Agelena (Eurasian grass spiders) a genus of similar spiders, and Greek -opsis "to look like". They are harmless spiders. Although most spiders use their webs to catch prey, the grass spider's web lacks adhesive ability. The spiders make up for that with their fast running.

The main distinction between Agelenopsis and its European cousin genus Agelena consists of the pattern appearing on the cephalothorax: the former possess two quasi-parallel lines from the eyes to the beginning of the abdomen. The latter ones have lines that are curved, irregular and often meet at the end. Another difference is the length of the front legs row in females, however, in males the comparison is too inconsiderable.

Species

• Agelenopsis actuosa (Gertsch & Ivie, 1936) (USA, Canada) – Common American Funnel-web Spider or Canadian Funnel-web Spider
• Agelenopsis aleenae Chamberlin & Ivie, 1935 (USA)
• Agelenopsis aperta (Gertsch, 1934) (USA, Mexico) – Desert Grass Spider or North American Funnel-web Spider
• Agelenopsis emertoni Chamberlin & Ivie, 1935 (USA)
• Agelenopsis kastoni Chamberlin & Ivie, 1941 (USA)
• Agelenopsis longistyla (Banks, 1901) (USA)
• Agelenopsis naevia (Walckenaer, 1842) (USA, Canada)
• Agelenopsis oklahoma (Gertsch, 1936) (USA)
• Agelenopsis oregonensis Chamberlin & Ivie, 1935 (USA)
• Agelenopsis pennsylvanica (C. L. Koch, 1843) (USA) – Pennsylvania Grass Spider
• Agelenopsis potteri (Blackwall, 1846) (North America, introduced in Russia)
• Agelenopsis spatula Chamberlin & Ivie, 1935 (USA)
• Agelenopsis utahana (Chamberlin & Ivie, 1933) (USA, Canada, Alaska)

Other pictures

• Agelenidae male 17mm.jpg

  Agelenopsis sp. male, 17 mm (about ¾ inch)

• Agelenidae male palps 17mm.jpg

  Same, showing elaborate pedipalps

• Agelenidae male side.jpg

  Same, from the side

• Agelenopsis pennsylvanica female PEM.jpg

  Agelenopsis sp. showing pronounced leg spines

• Spider in corner.jpg

  Agelenopsis in its web

• Grass Spider on Long Island Maine Aug 2008.jpg

  Agelenopsis in web built on grass, with prey

References

• Platnick, N. I. (2007). The world spider catalog, version 7.5. American Museum of Natural History.

See also

Funnel-Web Spider

External links

• Agelenidae species
• Pictures of Agelenopsis sp. (free for noncommercial use)
• Diagnostic Photos and information, Agelenopsis sp.
• Common Spiders in California, Agelenopsis sp.