Spiny orb-weaver
Gasteracantha is a genus of orb-weaver spiders first named by Carl Jakob Sundevall in 1833. The females of most species are brightly colored with six prominent spines on their broad, hardened, shell-like abdomens. The name Gasteracantha is derived from the Greek gaster, meaning "belly, abdomen", and akantha, meaning "thorn, spine". Spiny-backed orb-weavers are sometimes colloquially called "crab spiders" because of their shape, but they are not closely related to the true crab spiders. Other colloquial names for certain species include thorn spider, star spider, kite spider, or jewel spider.
Members of the genus exhibit strong sexual dimorphism. Males are several times smaller than females, and they lack prominent spines or bright colors.
Gasteracantha is distributed worldwide in tropical and subtropical climates. The genus is most diverse in tropical Asia, from India through Indonesia. One species, G. cancriformis, occurs in the Americas. Gasteracantha species are related to spine-bearing orb-weavers in several other genera.
Orb-weavers' bites are generally harmless to humans.
Taxonomy and systematics
Gasteracantha has a complex taxonomic history, and many questions of species limits and distribution and generic interrelationships remain unanswered. Challenges include the variability within individual Gasteracantha species, a lack of male specimens and descriptions for many species, missing or damaged type specimens, and ambiguous initial descriptions in 18th- and 19th-century scientific literature. The 70 species currently recognized by World Spider Catalog include dozens of synonyms and subspecies, many based on literature well over 100 years old.Gasteracantha is related to several other spiny orb-weaver genera of Africa, Asia, and Australasia, many of which are monospecific:
- Acrosomoides – 3 spp., Africa
- Actinacantha – Actinacantha globulata, Indonesia
- Aetrocantha – Aetrocantha falkensteini, central Africa
- Afracantha – Afracantha camerunensi, Africa
- Augusta – Augusta glyphica, Madagascar
- Austracantha – Austracantha minax, Australia
- Friula – Friula wallacei, Borneo
- Gastroxya – 4 spp., Africa
- Hypsacantha – Hypsacantha crucimaculata, Africa
- Isoxya – 16 spp., Africa, Madagascar, and Yemen
- Macracantha – 1 or 2 spp., Asia
- Madacantha – Madacantha nossibeana, Madagascar
- Parmatergus – 3 spp., Madagascar
- Thelacantha – Thelacantha brevispina, Australia, Asia, Madagascar
- Togacantha – Togacantha nordviei, Africa
Micrathena orb-weavers in North and South America also have hardened abdomens with variously shaped spines, but they are not closely related to Gasteracantha within the orb-weaver family.
Gallery
Species
Gasteracantha contains 70 species and 33 subspecies:- G. aciculata – Papua New Guinea
- G. acutispina Dahl, 1914 – Indonesia
- G. audouini Guérin, 1838 – Indonesia, Philippines
- G. aureola Mi & Peng, 2013 – China
- G. beccarii Thorell, 1877 – Indonesia
- G. biloba – Indonesia
- G. cancriformis – North America, Central America, Caribbean, South America. Introduced to Hawaii
- *Gasteracantha c. gertschi Archer, 1941 – USA
- G. clarki Emerit, 1974 – Seychelles
- G. clavatrix – Indonesia
- G. clavigera Giebel, 1863 – Thailand, Philippines, Indonesia
- G. crucigera Bradley, 1877 – Malaysia, Indonesia, New Guinea
- G. curvispina – West, Central Africa
- G. curvistyla Dahl, 1914 – Indonesia
- G. cuspidata C. L. Koch, 1837 – Malaysia, India, Indonesia
- G. dalyi Pocock, 1900 – India, Pakistan
- G. diadesmia Thorell, 1887 – India to Philippines
- G. diardi – China, Thailand, Malaysia, Borneo, Indonesia
- G. doriae Simon, 1877 – Singapore, Indonesia
- G. falcicornis Butler, 1873 – Africa
- G. fasciata Guérin, 1838 – New Guinea, Guam
- G. flava Nicolet, 1849 – Chile
- G. fornicata – Australia
- G. frontata Blackwall, 1864 – India, Myanmar, Thailand, Indonesia
- G. gambeyi Simon, 1877 – New Caledonia
- G. geminata – India, Sri Lanka
- G. hasselti C. L. Koch, 1837 – India, China to Indonesia
- G. hecata – Philippines
- G. interrupta Dahl, 1914 – Indonesia
- G. irradiata – Thailand to Philippines, Indonesia
- G. janopol Barrion & Litsinger, 1995 – Philippines
- G. kuhli C. L. Koch, 1837 – India to Japan, Philippines
- G. lepelletieri – Indonesia to Philippines, New Guinea
- G. lunata Guérin, 1838 – Timor, Indonesia, New Caledonia
- G. martensi Dahl, 1914 – Indonesia
- G. mediofusca – Indonesia, New Guinea
- G. mengei Keyserling, 1864 – Malaysia, Indonesia
- G. metallica – Solomon Is.
- G. milvoides Butler, 1873 – Central, East, Southern Africa
- G. notata Kulczyński, 1910 – Papua New Guinea
- G. panisicca Butler, 1873 – Myanmar to Philippines, Indonesia
- G. parangdiadesmia Barrion & Litsinger, 1995 – Philippines
- G. pentagona – Papua New Guinea
- *Gasteracantha p. anirica Strand, 1915 – Papua New Guinea
- G. picta – Singapore
- G. quadrispinosa O. Pickard-Cambridge, 1879 – New Guinea, Australia
- G. recurva Simon, 1877 – Philippines
- G. regalis Butler, 1873 – Vanuatu
- G. remifera Butler, 1873 – India, Sri Lanka
- G. rhomboidea Guérin, 1838 – Mauritius
- *Gasteracantha r. comorensis Strand, 1916 – Comoros, Mayotte
- *Gasteracantha r. madagascariensis Vinson, 1863 – Madagascar
- G. rubrospinis Guérin, 1838 – Indonesia, New Caledonia, Guam
- G. rufithorax Simon, 1881 – Madagascar
- G. sacerdotalis L. Koch, 1872 – New Guinea, Australia, New Caledonia
- G. sanguinea Dahl, 1914 – Philippines
- G. sanguinolenta C. L. Koch, 1844 – Africa, Yemen, Seychelles
- *Gasteracantha s. andrefanae Emerit, 1974 – Madagascar
- *Gasteracantha s. bigoti Emerit, 1974 – Madagascar
- *Gasteracantha s. emeriti Roberts, 1983 – Seychelles
- *Gasteracantha s. insulicola Emerit, 1974 – Seychelles
- *Gasteracantha s. legendrei Emerit, 1974 – Europa Is.
- *Gasteracantha s. mangrovae Emerit, 1974 – Madagascar
- *Gasteracantha s. rueppelli Strand, 1916 – Egypt
- G. sapperi Dahl, 1914 – New Guinea
- G. sauteri Dahl, 1914 – China, Taiwan, Vietnam
- G. scintillans Butler, 1873 – Solomon Is.
- G. signifera Pocock, 1898 – Solomon Is.
- *Gasteracantha s. bistrigella Strand, 1911 – Papua New Guinea
- *Gasteracantha s. heterospina Strand, 1915 – Papua New Guinea
- *Gasteracantha s. pustulinota Strand, 1911 – Papua New Guinea
- G. simoni O. Pickard-Cambridge, 1879 – Central Africa
- G. sororna Butler, 1873 – India
- G. sturi – Laos, Sumatra, Java, Borneo, Moluccas
- G. subaequispina Dahl, 1914 – Borneo, New Guinea
- G. taeniata – India to Polynesia
- *Gasteracantha t. analispina Strand, 1911 – New Guinea
- *Gasteracantha t. anirensis Strand, 1911 – Papua New Guinea
- *Gasteracantha t. bawensis Strand, 1915 – New Guinea
- *Gasteracantha t. jamurensis Strand, 1915 – New Guinea
- *Gasteracantha t. lugubris Simon, 1898 – Solomon Is.
- *Gasteracantha t. maculella Strand, 1911 – Indonesia
- *Gasteracantha t. novahannoveriana Dahl, 1914 – Papua New Guinea
- *Gasteracantha t. obsoletopicta Strand, 1915 – Indonesia
- *Gasteracantha t. oinokensis Strand, 1915 – New Guinea
- *Gasteracantha t. sentanensis Strand, 1915 – New Guinea
- *Gasteracantha t. trivittinota Strand, 1911 – Papua New Guinea
- *Gasteracantha t. univittinota Strand, 1911 – Papua New Guinea
- G. theisi Guérin, 1838 – New Guinea, Indonesia
- *Gasteracantha t. antemaculata Strand, 1911 – Indonesia
- *Gasteracantha t. keyana Strand, 1911 – Indonesia
- *Gasteracantha t. quadrisignatella Strand, 1911 – Indonesia
- G. thomasinsulae Archer, 1951 – São Tomé and Príncipe
- G. thorelli Keyserling, 1864 – Madagascar
- G. tondanae Pocock, 1897 – Indonesia
- G. transversa C. L. Koch, 1837 – Indonesia
- G. unguifera Simon, 1889 – China, India
- G. versicolor – Central, East, Southern Africa
- *Gasteracantha v. avaratrae Emerit, 1974 – Madagascar
- *Gasteracantha v. formosa Vinson, 1863 – Madagascar
- G. westringi Keyserling, 1864 – Australia, Admiralty Is., New Caledonia