Orb-weaver spiders are members of the spider family Araneidae. They are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields, and forests. The English word "orb" can mean "circular", hence the English name of the group. Araneids have eight similar eyes, hairy or spiny legs, and no stridulating organs.
Eriophora is a genus of orb-weaver spiders first described by Eugène Simon in 1895. It occurs in the Americas, Australasia, and Africa. The name is derived from Ancient Greek roots, and means "wool bearing".
Aculepeira ceropegia, the oak spider, is an orb-weaving spider species belonging to the family Araneidae.
Aculepeira is a genus of orb-weaver spiders first described by R. V. Chamberlin & Wilton Ivie in 1942.
Ordgarius is a genus of orb-weaver spiders first described by Eugen von Keyserling in 1886. Adult females of the genus are bolas spiders, capturing their prey with one or more sticky drops at the end of a single line of silk rather than in a web. Males and juvenile females capture their prey directly with their legs.
Micrathena, known as spiny orbweavers, is a genus of orb-weaver spiders first described by Carl Jakob Sundevall in 1833. Micrathena contains more than a hundred species, most of them Neotropical woodland-dwelling species. The name is derived from the Greek "micro", meaning "small", and the goddess Athena.
Dolichognatha is a genus of tropical and subtropical long-jawed orb-weavers that was first described by Octavius Pickard-Cambridge in 1869. Originally placed with the Archaeidae, it was transferred to the Araneidae in 1967, and to the Tetragnathidae in 1981.
Acacesia is a genus of orb-weaver spiders first described by Eugène Simon in 1895. It contains six species with a mostly neotropical distribution, ranging from South America to Mexico. One species, A. hamata, is found in the US as well.
Metepeira is a genus of orb-weaver spiders first described by F. O. Pickard-Cambridge in 1903. The name is derived from the Ancient Greek μετά and the obsolete genus name Epeira, denoting a genus similar to Epeira.
Glenognatha is a genus of long-jawed orb-weavers that was first described by Eugène Louis Simon in 1887. It was considerably revised in 2016.
Mastophora, also known as bolas spiders, is a genus of orb-weaver spiders first described by E. L. Holmberg in 1876. They can be identified by a pair of lumps on the dorsal surface of the opisthosoma, though not all males will have these lumps.
Parawixia is a genus of orb-weaver spiders first described by F. O. Pickard-Cambridge in 1904. Most species are found in the Neotropics but one species, Parawixia dehaani, is found in Australasia and tropical Asia as far west as India.
Allocyclosa is a genus of orb weaver spiders that contains only one species, Allocyclosa bifurca. It was first described in 1887 by McCook under the name Cyrtophora bifurca, and was transferred to its own genus in 1999. It is the only Cyclosa species north of Mexico to have a forked tail, hence the name bifurca, Latin for "two-forked". The forked abdomen, bearing two humps shaped like the letter M, is a defining feature in both males and females, though it is similar to features present in certain Cyrtophora species. Both sexes are a transparent green color, though only females have an area of red on their underside between the epigynum and the spinnerets. Females are nearly thirty percent larger than males, ranging from five to nine millimeters, while males range from two to three millimeters. Males are very uncommon. In a 1977 study by Levi, only two of the nearly 350 specimens that were positively identified as Cyrtophora bifurca were males. This is a very odd distribution, and it has been posed that females of the species, which have less prominent genitalia relative to other members of the orb-weaver family, may be parthenogenic, or able to reproduce without the help of males. Like other members of Araneidae, these spiders create orb webs, six to eight inches in diameter, but apply a unique form of protective mimicry. Females sit in the middle of a vertical row of web decoration, with egg sacs above and wrapped prey below. Because they all have a similar color and shape, it is difficult to discern between the egg sacs, the wrapped prey, and the spider itself.
Kapogea is a genus of orb-weaver spiders first described by Herbert Walter Levi in 1997.
Metazygia is a genus of orb-weaver spiders first described by F. O. Pickard-Cambridge in 1904. They physically resemble members of Nuctenea, but they do not have fine setae on the carapace.
Wagneriana is a genus of orb-weaver spiders first described by F. O. Pickard-Cambridge in 1904.
Azilia is a genus of long-jawed orb-weavers that was first described by Eugen von Keyserling in 1881. It is a senior synonym of Cardimia.
Mastophora extraordinaria is a species of spider in the orb-weaver spider family Araneidae. It is found in South America. Like some other species of the genus Mastophora, adult females resemble bird droppings. Mastophora species, including M. extraordinaria, are "bolas spiders" – adult females capture their prey by using a sticky drop on the end of a single line which they swing at the target, usually a male moth attracted by the release of an analogue of the attractant sex pheromone produced by the female moth. Juveniles and adult males do not use a bolas, catching prey with their legs alone.
