Widow Spider
( Theridiidae )


2011-0511-SP111001-ARA01466-Theridiidae[1646h05s,F,A,post]{SPeden}-G.jpg

PHOTO COMMENT

IDENTIFICATION
Identification:Theridiidae
(Sundevall, 1833)
Common Name:Widow Spider
Life Stage:(A) adult

PHYLOGENY

Phylum:Arthropoda
Class:Arachnida
Order:Araneae
Family:Theridiidae
Genus:Genera Achaearanea, Anelosimus, and Theridion are known to contain subsocial species, but the only social spiders in America north of Mexico are in the genus Anelosimus.
Taxon Code:ARA01466
ITIS TSN#:82740

LOCATION DETAILS
Location
Henry Cowell Redwoods SP, Henry Cowell Redwoods SP, 101 North Big Trees Park Road, Felton
County:Santa Cruz County
ECI Site#:CASP111001
Park/Forest:Henry Cowell Redwoods SP

RECOGNITION
In separating Theridiidae from Linyphiidae: 1. Legs Theridiidae have first legs usually longest, third legs shortest. Also fourth legs usually with comb macrosetae (indistinct in Dipoena & Euryopis). Legs have no thick setae and no femoral macrosetae. Linyphiidae have legs long & thin with macrosetae. (Hairs on males somewhat reduced.) They have long sensory hairs on the first three legs, sometimes on all four legs. 2. Abdomen Theridiidae have abdomen usually round, rarely elongate. Linyphiidae abdomen usually oval or elongated.

BIOLOGY
Food
Spiders with very small (if strong) jaws (such as crab spiders and cobweb weavers) make small holes in the prey and vomit their digestive fluid into the prey's body, the end result being a hollow shell with some or most of the muscles and internal organs digested and sucked out.

HABITAT

CREDITS
Photographer
Scott Peden

REFERENCES
  • Family Theridiidae - Cobweb Spiders. (http://bugguide.net/node/view/1960). Accessed March 12, 2016. [ IMAGES ]
  • Integrated Taxonomic Information System TSN#82740


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