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Species Gasteracantha cancriformis - Spinybacked Orbweaver

Crab Spider - Gasteracantha cancriformis Crablike Spiny Orbweaver Spider - Gasteracantha cancriformis Crablike Spiny Orb Weaver - Gasteracantha cancriformis - female Texas spiders - Gasteracantha cancriformis Happy Face - Gasteracantha cancriformis Yellow Smiley Face Crab Spider - Gasteracantha cancriformis Crablike Spiny Orbweaver Spider - Gasteracantha cancriformis Gasteracantha cancriformis Horned Spider - Gasteracantha cancriformis Thorny-orbed Spider-- underside - Gasteracantha cancriformis
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynae)
Family Araneidae (Orb Weavers)
Genus Gasteracantha
Species cancriformis (Spinybacked Orbweaver)
Other Common Names
Crab Spider, Spiny Orbweaver Spider, Crab-like Orbweaver Spider, Crab-like Spiny Orbweaver Spider, Jewel Spider, Spiny-bellied Orbweaver, Jewel Box Spider, Smiley Face Spider, Crablike Spiny Orbweaver.
Synonyms and other taxonomic changes
G. elipsoides
Explanation of Names
Gasteracantha cancriformis (Linnaeus, 1758)
cancriformis (L), 'crab shaped' (1)
This species can be easily distinguished from all other spiders. Females may be 5 to nearly 9 mm in length, but 10 to 13 mm wide. They have six pointed abdominal projections frequently referred to as "spines." The carapace, legs, and venter are black, with some white spots on the underside of the abdomen. The dorsum of the abdomen is, typically for Florida specimens, white with black spots and red spines. Specimens from other areas may have the abdominal dorsum yellow instead of white, may have black spines instead of red, or may be almost entirely black dorsally and ventrally.

Males are much smaller than females, 2 to 3 mm long, and slightly longer than wide. Color is similar to the female, except the abdomen is gray with white spots. The large abdominal spines are lacking, although there are four or five posterior small humps (Levi 1978, Muma 1971).
This species is primarily found in the southeastern US, CA (TX-FL-MD-OK) / south through much of the New World, including some islands, including much of the Greater Antilles and some of the Bahamian islands. (Levi, 1978),(BG data)
It lives in woodland edges and shrubby gardens. Many of the studies on this spider have taken place in citrus groves in Florida. They frequently live in trees or around trees in shrubs. (Levi, 1978)
This species is mostly found from May-Dec but year-round in FL (BG data)
Life Cycle
This species of spider does not live very long. In fact, the lifespan only lasts until reproduction, which usually takes place the spring following the winter when they hatched. Females die after producing an egg mass, and males die six days after a complete cycle of sperm induction to the female.
This spider adds little tufts of silk to its web. According to Florida's Fabulous Spiders(2) "these little flags serve a warning function to prevent birds from flying into the web, destroying it."
Internet References
Texas Entomology - Mike Quinn, 2008
Works Cited
1.Dictionary of Word Roots and Combining Forms
Donald J. Borror. 1960. Mayfield Publishing Company.
2.Florida's Fabulous Spiders
Sam Marshall, G. B. Edwards. 2002. World Publications.