Gasteracantha cancriformis

Gasteracantha cancriformis
Female
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Araneidae
Genus:	Gasteracantha
Species:	G. cancriformis
Binomial name
Gasteracantha cancriformis (Linnaeus, 1758) [1]
Synonyms
Aranea cancriformisLinnaeus, 1758 Aranea conchataSlabber, 1769 Aranea tetracanthaLinnaeus, 1767 Dicantha lata(Walckenaer, 1805) Epeira cancerHentz, 1850 Epeira lataWalckenaer, 1805 Epeira servilleiGuérin, 1825 Gasteracantha biolleyiBanks, 1905 Gasteracantha callidaO. Pickard-Cambridge, 1879 Gasteracantha canestriniiO. Pickard-Cambridge, 1879 Gasteracantha columbiaeGiebel, 1863 Gasteracantha comstockiMello-Leitão, 1917 Gasteracantha ellipticaGétaz, 1893 Gasteracantha hilarisThorell, 1859 Gasteracantha insulanaThorell, 1859 Gasteracantha kochiiButler, 1873 Gasteracantha mammosaC. L. Koch, 1844 Gasteracantha masculaStrand, 1916 Gasteracantha mauraMcCook, 1894 Gasteracantha moestaThorell, 1859 Gasteracantha oldendorffiiHolmberg, 1876 Gasteracantha pallidaC. L. Koch, 1844 Gasteracantha piceaC. L. Koch, 1844 Gasteracantha preciosaMcCook, 1894 Gasteracantha proboscideaTaczanowski, 1879 Gasteracantha quadridensC. L. Koch, 1844 Gasteracantha raimondiiTaczanowski, 1879 Gasteracantha rubiginosaC. L. Koch, 1844 Gasteracantha rufospinosaMarx, 1886 Gasteracantha servillei(Guérin, 1825) Gasteracantha tetracantha(Linnaeus, 1767) Gasteracantha velitarisC. L. Koch, 1837 Micrathena triserrata(Walckenaer, 1841) Plectana atlanticaWalckenaer, 1841 Plectana cancriformis(Linnaeus, 1758) Plectana elipsoidesWalckenear, 1841 Plectana lata(Walckenaer, 1805) Plectana quinqueserrataWalckenaer, 1841 Plectana servillei(Guérin, 1825) Plectana sexserrataWalckenaer, 1841 Plectana triserrataWalckenaer, 1841 Plectana velitaris(C. L. Koch, 1837) Vibradellus carolinusChamberlin, 1925

Gasteracantha cancriformis ^[2] (spinybacked orbweaver) is a species of orb-weaver spider (family Araneidae). It is widely distributed in the New World. ^[1]

The genus name Gasteracantha derives from the Ancient Greek γαστήρ (gastḗr), meaning "belly", and ἄκανθα (ákantha), meaning "thorn", while the specific epithet cancriformis derives from the Latin words cancer ("crab") and forma ("shape, form, appearance").

Description

Females are 5–9 mm (0.20–0.35 in) long and 10–13 mm (0.39–0.51 in) wide. The six abdominal spine-like projections on the abdomen are characteristic. The carapace, legs, and underside are black with white spots under the abdomen. Variations occur in the colour of the upperside of the abdomen - a white or yellow colour with both featuring black spots. A white upper side can have either red or black spines while a yellow upperside can only have black ones. Like with many other spiders, males are much smaller (2 to 3 mm long) and longer than wide. All morphs have six abdominal spines. ^{[3] [4]} They are similar to the females in colour, but have a gray abdomen with white spots and the spines are reduced to four or five stubby projections.

This species of spider does not live very long. In fact, the lifespan lasts only until reproduction, which usually takes place in 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.

Distribution and habitat

G. cancriformis is native to North America, Central America, the Caribbean and South America. ^[1] It has been introduced elsewhere, including Hawaii. It prefers living around the edge of woodland and shrubby gardens. Many studies about G. cancriformis are performed in citrus groves in Florida. ^{[1] [5]}

G. cancriformis is seen to coexist within and on the edges of the colonies of other colonial orb-weaver spiders, mainly Metepeira incrassata . M. incrassata is known to form large colonies ranging from few hundreds to few thousands of spiders, and their colonies often accommodate other species of orb-weavers including G. cancriformis. ^[6]

Taxonomy

G. cancriformis has two subspecies, G. c. cancriformis and G. c. gertschi. ^[7]

Gallery

• 
  Eating a butterfly
• 
  Ventral view, with spinneret visible
• 
  In Miami
• 
  In Miami Lakes
• 
  In Ecuador
• 
  In Novo Hamburgo (southern Brazilian population), with focus on the web
• Mating in the Summer
• 
  On a tufted web in Houston, Texas
• 
  Color variation, near Houston
• 
  Underside of orange specimen, showing spinner and thread. For scale, band in background is 6 mm wide. Near Houston
• 
  In Molokai, Hawaii
• 
  Ventral view, in North Carolina

See also

• Thelacantha brevispina
• Austracantha minax

References

1. "Taxon details Gasteracantha cancriformis (Linnaeus, 1758)", World Spider Catalog, Natural History Museum Bern, retrieved 2016-04-28
2. Peters, A. (2002). "Gasteracantha cancriformis". animaldiversity.org. Animal Diversity Web.
3. Levi, 1978
4. Muma, 1971
5. Peters, Annie. "Gasteracantha cancriformis". Animal Diversity Web. Retrieved 2021-10-27.
6. Hodge, Margaret A.; Uetz, George W. (September 1996). "Foraging advantages of mixed-species association between solitary and colonial orb-weaving spiders" . Oecologia. 107 (4): 578–587. Bibcode:1996Oecol.107..578H. doi:10.1007/BF00333951. ISSN   0029-8549. PMID   28307403. S2CID   13382984.
7. Archer, Allan F. (1941). "Supplement to the Argiopidae of Alabama" (PDF). Geological Survey of Alabama. Museum Paper 18: 23–25.

Further reading

• Eberhard, William G. (2006): Stabilimenta of Philoponella vicina (Araneae: Uloboridae) and Gasteracantha cancriformis (Araneae: Araneidae): Evidence Against a Prey Attractant Function. Biotropica39(2): 216-220. doi : 10.1111/j.1744-7429.2006.00254.x

External links

Media related to Gasteracantha cancriformis at Wikimedia Commons