HomeGuideID RequestRecentFrassForumsDonateHelp

Clickable Guide

Calendar

Upcoming Events

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

National Moth Week was July 23-31, 2022! See moth submissions.

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

Photos of insects and people from the 2019 gathering in Louisiana, July 25-27

Photos of insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Previous events

TaxonomyBrowse

Info

ImagesLinksBooksData

Home » Guide » Arthropods (Arthropoda) » Chelicerates (Chelicerata) » Arachnids (Arachnida) » Spiders (Araneae) » True Spiders (Araneomorphae) » Entelegynae » Cheiracanthiidae » Long-legged Sac Spiders (Cheiracanthium) » Cheiracanthium mildei

Species Cheiracanthium mildei

Classification · Other Common Names · Synonyms and other taxonomic changes · Explanation of Names · Size · Identification · Range · Habitat · Season · Food · Life Cycle · Remarks · Works Cited

Gray Sac Spider? - Cheiracanthium mildei - female

Cheiracanthium mildei? - Cheiracanthium mildei - female

I think this is a sac spider - Cheiracanthium mildei

yellow sac spider - Cheiracanthium mildei - female

yellowish spider - Cheiracanthium mildei

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Subphylum Chelicerata (Chelicerates)

Class Arachnida (Arachnids)

Order Araneae (Spiders)

Infraorder Araneomorphae (True Spiders)

No Taxon (Entelegynae)

Family Cheiracanthiidae

Genus Cheiracanthium (Long-legged Sac Spiders)

Species mildei (Cheiracanthium mildei)

Other Common Names

Yellow Sac Spider, Black-footed Spider

Synonyms and other taxonomic changes

See the World Spider Catalog.

Explanation of Names

Author: C. L. Koch, 1839

Size

7-10 mm

Identification

C. mildei is a relatively small, pale greenish, tan or straw-colored spider. Its front pair of legs is longer than the others, and all four pairs end in double claws.

Male:

The male can be recognized by having a pedipalp with 2 equally long tibial apophyses. (C. inclusum appears to have one short apophysis and one long apophysis.)

Female:

epigyne

Range

Holarctic distribution as well as southern South America (Argentina).

Habitat

They make a resting tube in a rolled leaf or under bark or stones. (1)

More often found inside man-made structures (as opposed to C. inclusum which is found more often outdoors). Habitat is not the best way to separate them, though; genitalia needs to be examined under microscope.

Season

Indoor populations of C. mildei are non-seasonal and can be adult at any time.

Food

Any small invertebrate (e.g. insects).

Life Cycle

After mating, females lay 30-48 eggs, cover them in a thin, white silken sac and guard them. The egg sacs may be found in protected areas, or even wrapped in a folded leaf. All stages of sac spiders make a silken cell (the "sac"), in which they rest when not active.

Remarks

Being Bitten:

Yellow sac spider bites occur most frequently when the very defensive spider is trapped in clothing.

As Rod Crawford points out, "It turned out that the association of this spider with blisters and lesions was wrong, though accepted by everyone until recently. See the attached paper. I'd say this species ought to be taken off the medical concern list." See full article here.

Sac spiders are classified as hunting spiders. These spiders are very active at night and will emerge from their day resting sacs to run along walls and ceilings in pursuit of prey. If startled, they drop down on draglines and scurry away!

Imported from Europe in the 1940s.

Works Cited

1.	Spiders and Their Kin: A Golden Guide from St. Martin's Press Herbert W. Levi, Lorna R. Levi, Nicholas Strekalovsky. 2001. St. Martin's Press.

Contributed by Troy Bartlett on 13 April, 2004 - 6:01pm
Additional contributions by Lynette Elliott, Christopher Hunt, cheins, dragonfly12, jsloan, Mandy Howe, Laura P.
Last updated 20 May, 2022 - 12:49pm

Disclaimer: Dedicated naturalists volunteer their time and resources here to provide this service. We strive to provide accurate information, but we are mostly just amateurs attempting to make sense of a diverse natural world. If you need expert professional advice, contact your local extension office.

Contributors own the copyright to and are solely responsible for contributed content.
Click the contributor's name for licensing and usage information.
Everything else copyright © 2003-2023 Iowa State University, unless otherwise noted.

Bugguide is hosted by:

Printer Friendly Version