This article includes a list of general references, but it lacks sufficient corresponding inline citations .(January 2014) |
Steatoda Temporal range: | |
---|---|
Female Steatoda bipunctata | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Chelicerata |
Class: | Arachnida |
Order: | Araneae |
Infraorder: | Araneomorphae |
Family: | Theridiidae |
Genus: | Steatoda Sundevall, 1833 [1] |
Species | |
Diversity [1] | |
120 species |
The spider genus Steatoda, in the family Theridiidae, includes about 120 recognized species, distributed around the world (including many cosmopolitan species which are found among human populations worldwide). [2] One common name is cupboard spider, for many species build their webs in dark, sheltered, undisturbed places around the house or garden, in sheds and garages, under garden, in compost bins, and the like. Signs of the cupboard spider include small white spots of spider droppings, like small splashes of paint, on the floor underneath the web. [3]
Many spiders of the genus Steatoda are often mistaken for widow spiders ( Latrodectus ), and are known as false widows. The two genera are closely related – both occurring in the same family, Theridiidae – but Steatoda are significantly less harmful to humans. Not all Steatoda species resemble black widows – they come in many different colors and sizes, mostly smaller than Latrodectus species. Steatoda paykulliana can grow larger than the black widow, and Steatoda castanea looks more like a brown widow.
The colour can range from sandy pale brown to reddish plum to satiny black. Like most spiders, its cephalothorax is smaller than its abdomen, which is somewhat egg-shaped, and can have white or beige to orange markings. Although sometimes not or partially visible, these markings usually consists of a frontal crescent, often with a dorsal line or triangular shapes or both. Orange to reddish-marked Steatoda paykulliana can be mistaken for the redback spider).
In common with other members of the family Theridiidae, Steatoda construct a tangled web, i.e., an irregular tangle of sticky silken fibers. These spiders have very poor eyesight and depend mostly on vibrations reaching them through their webs to orient themselves to prey or to warn them of larger animals that could injure or kill them.
As of May 2024 [update] , the World Spider Catalog accepted the following extant species: [1]
Those commonly mistaken for widows include:
Other notable and recognizable species in the genus include:
Steatoda is known to prey on other spiders (including true black widows), crickets, ladybugs, cockroaches, and woodlice. [9]
Some members of this genus do have bites which are reported to have generalized symptoms in humans (such as S. grossa and S. nobilis ). [10] However total number of cases are rare with one ever in France and England each, and 5 in Ireland. A review by Isbister noted 23 over 3 years in Australia. No bites require medical treatment. However, bites by Steatoda species generally do not have any long-lasting effects. Symptoms can include moderate to severe pain increasing for the first hour (without severe sweating). [10] Some people have reported mild to moderate nausea, headache, and lethargy. [11] The duration of all symptoms and effects can range from 1 to 60 hours. [12] [13]
The symptoms associated with the bite of several Steatoda species have been named steatodism; and have been described as a less-severe form of latrodectism (the symptoms associated with a widow spider bite). The redback spider antivenom has been thought to be effective at treating bites from S. grossa, after it was mistakenly administered to a S. grossa bite victim who was erroneously believed to have been bitten by the far more dangerous redback. (While the redback antivenom appears clinically active against arachnidism caused by Steatoda spiders, [68] [100] [101] [102] as these cases are often mild and the evidence of its effectiveness is limited, this treatment is not recommended.) [90]
Steatoda spiders are not aggressive, and most injuries to humans are due to defensive bites delivered when a spider is squeezed or pinched. It is possible that some bites result when a spider mistakes a finger thrust into its web for another arthropod, but intrusion by any large creature will cause these spiders to flee.
Latrodectus is a broadly distributed genus of spiders with several species that are commonly known as the true widows. This group is composed of those often loosely called black widow spiders, brown widow spiders, and similar spiders. However, the diversity of species is much greater. A member of the family Theridiidae, this genus contains 34 species, which include several North American "black widows". Besides these, North America also has the red widow Latrodectus bishopi and the brown widow Latrodectus geometricus, which, in addition to North America, has a much wider geographic distribution. Elsewhere, others include the European black widow, the Australian redback spider and the closely related New Zealand katipō, several different species in Southern Africa that can be called button spiders, and the South American black-widow spiders. Species vary widely in size. In most cases, the females are dark-coloured and can be readily identified by reddish markings on the central underside (ventral) abdomen, which are often hourglass-shaped.
Theridiidae, also known as the tangle-web spiders, cobweb spiders and comb-footed spiders, is a large family of araneomorph spiders first described by Carl Jakob Sundevall in 1833. This diverse, globally distributed family includes over 3,000 species in 124 genera, and is the most common arthropod found in human dwellings throughout the world.
Steatoda grossa, commonly known as the cupboard spider, the dark comb-footed spider, the brown house spider, or the false widow or false black widow, is a common species of spider in the genus Steatoda.
Steatoda nobilis is a spider in the genus Steatoda, known in the United Kingdom as the noble false widow, as it superficially resembles and is frequently mistaken for the black widow and other spiders in the genus Latrodectus. It is often referred to as thefalse widow, although "false widow" is a more general term applied to a wider group of species with this resemblance.[a] It is a moderately medically significant spider, with most bites resulting in symptoms similar to a bee or wasp sting. Some bites may cause more significant harm, partly due to pathogenic bacteria from the spiders.
Episinus is a genus of comb-footed spiders that was first described by Pierre André Latreille in 1809.
Cyclosa, also called trashline orbweavers, is a genus of orb-weaver spiders first described by Anton Menge in 1866. Widely distributed worldwide, spiders of the genus Cyclosa build relatively small orb webs with a web decoration. The web decoration in Cyclosa spiders is often linear and includes prey remains and other debris, which probably serve to camouflage the spider. The name "Cyclosa" comes from Greek 'to move in a circle', referring to how it spins its web.
Theridion is a genus of tangle-web spiders with a worldwide distribution. Notable species are the Hawaiian happy face spider (T. grallator), named for the iconic symbol on its abdomen, and T. nigroannulatum, one of few spider species that lives in social groups, attacking prey en masse to overwhelm them as a team.
Clubiona is a genus of sac spiders that was first described by Pierre André Latreille in 1804.
Thwaitesia is a genus of comb-footed spiders that was first described by Octavius Pickard-Cambridge in 1881.
Tetragnatha is a genus of long-jawed orb-weavers found all over the world. It was first described by Pierre André Latreille in 1804, and it contains hundreds of species. Most occur in the tropics and subtropics, and many can run over water. They are commonly called stretch spiders in reference to their elongated body form and their ability to hide on blades of grass or similar elongated substrates by stretching their front legs forward and the others behind them. The name Tetragnatha is derived from Greek, tetra- a numerical prefix referring to four and gnatha meaning jaw. Evolution to cursorial behavior occurred long ago in a few different species, the most studied being those found on the Hawaiian islands. One of the biggest and most common species is T. extensa, which has a holarctic distribution. It can be found near lakes, river banks or swamps. Large numbers of individuals can often be found in reeds, tall grass, and around minor trees and shrubs.
Steatoda capensis is a spider originating from South Africa. Its common names include the black cobweb spider, brown house spider, cupboard spider and due to its similarities to the katipō spider it is commonly known as the false katipō in New Zealand. Common throughout Southern Africa, it has been introduced into other countries and is now present in Australia and throughout New Zealand. It is a small spider, usually an all-over shiny black. It may have a small bright red, orange, or yellow patch near the tip of the abdomen along with a crescent shaped band near the front of the abdomen.
Crustulina is a genus of comb-footed spiders that was first described by Anton Menge in 1868.
Euryopis is a genus of comb-footed spiders that was first described by Anton Menge in 1868.
Dipoena is a genus of tangle-web spiders that was first described by Tamerlan Thorell in 1869.
Phoroncidia is a genus of comb-footed spiders that was first described by J. O. Westwood in 1835.
Rhomphaea is a genus of comb-footed spiders that was first described by Ludwig Carl Christian Koch in 1872.