Araneoidea is a

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

araneomorph The Araneomorphae (also called the Labidognatha or "true spiders") are an infraorder of spiders. They are distinguishable by chelicerae (fangs) that point diagonally forward and cross in a pinching action, in contrast to the Mygalomorphae (taran ...

spiders, termed "araneoids", treated as a

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

. As with many such groups, its

circumscription Circumscription may refer to: * Circumscribed circle * Circumscription (logic) *Circumscription (taxonomy) * Circumscription theory, a theory about the origins of the political state in the history of human evolution proposed by the American anthr ...

has varied; in particular some families that had at one time been moved to the

Palpimanoidea The Palpimanoidea or palpimanoids, also known as assassin spiders, are a group of araneomorph spiders, originally treated as a superfamily. As with many such groups, its circumscription has varied. , the following five families were included: * ...

have more recently been restored to Araneoidea. A 2014 treatment includes 18 families, with the araneoids making up about 26% of the total number of known spider

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

; a 2016 treatment includes essentially the same taxa, but now divided into 17 families.

Taxonomy

Many of the differences in circumscription concern the relationship between Araneoidea and

. In 1984, Raymond R. Forster and

Norman I. Platnick Norman Ira Platnick (December 30, 1951 – April 8, 2020) was an American biological systematist and Arachnology, arachnologist. At the time of his death, he was a professor emeritus of the American Museum of Natural History#Richard Gilder Gradua ...

proposed that some groups previously considered araneoid actually belonged in the distantly related Palpimanoidea, including the families Holarchaeidae, Micropholcommatidae, Mimetidae and Pararchaeidae. Subsequent phylogenetic studies have rejected this proposal, firmly placing these four families in Araneoidea (some included in other families).

Phylogeny

Although there is an increasing consensus on the

of Araneoidea, the relationship between many of its families remains uncertain. In 2014, Hormiga and Griswold produced the summary

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

shown below, based on what they considered to be the nine most comprehensive phylogenetic studies of Araneoidea prior to their article. Polytomies in the cladogram represent either conflicting results from the different studies or the absence of sufficiently comprehensive studies. A subsequent study by Dimitrov et al. in 2016 produced more resolved cladograms; their maximum likelihood cladogram based on the analysis of their entire dataset is shown below. Some of their other analyses produced different results; for example, a Bayesian analysis produced a monophyletic Anapidae rather than splitting it into two clades. They concluded that "the amount of information available to resolve these families is limited, particularly at the interfamilial and deeper levels. Only some of the interfamilial groupings ... were recovered with high support." One clade which is well supported is (Mimetidae + (Arkyidae + Tetragnathidae)). Both Hormiga and Griswold and Dimitrov et al. conclude that the sister taxon of Araneoidea is Nicodamidae s.l. (which Dimitrov et al. split into two families and call Nicodamoidea). It is likely that relationships will change further when more studies are carried out, since "currently available molecular and morphological data are insufficient to robustly resolve relationships".

Included families

After Dimitrov et al. 2016 *

Araneidae 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 ...

Anapidae Anapidae is a family of rather small spiders with 233 described extant species in 59 genera. It includes the former family Micropholcommatidae as the subfamily Micropholcommatinae, and the former family Holarchaeidae. Most species are less than ...

Arkyidae Arkyidae, also known as triangular spiders, is a family of araneomorph spiders first described by Ludwig Carl Christian Koch in 1872 as a subfamily of Araneidae, and later elevated to a full family in 2017. Genera and species This section lists ...

Cyatholipidae Cyatholipidae is a family of spiders first described by Eugène Simon in 1894. Most live in moist montane forest, though several species, including '' Scharffia rossi'', live in dry savannah regions. They occur in Africa, including Madagascar, Ne ...

Linyphiidae Linyphiidae, spiders commonly known as sheet weavers (from the shape of their webs), or money spiders (in the United Kingdom, Ireland, Australia, New Zealand, and Portugal) is a family of very small spiders comprising 4706 described species in 6 ...

Malkaridae Malkaridae is a small family of araneomorph spiders first described by Valerie Todd Davies in 1980. In 2017, the family Pararchaeidae was brought into synonymy with Malkaridae. Genera , the World Spider Catalog accepts the following genera: ...

Mimetidae Pirate spiders, members of the family Mimetidae, are araneomorph spiders which typically feed on other spiders. The family Mimetidae contains roughly 200 species divided among 12 genera, of which ''Mimetus'' and '' Ero'' are the most common. Mi ...

Mysmenidae Mysmenidae is a spider family with about 180 described species in seventeen genera. The family is one of the least well known of the orb-weaving spiders because of their small size () and cryptic behaviour. These spiders are found in humid habita ...

Nesticidae Scaffold web spiders or cave cobweb spiders (Nesticidae) are a family of araneomorph spiders closely allied with tangle-web spiders (Theridiidae). Like the Theridiidae, these spiders have a comb of serrated bristles on the hind tarsi that are u ...

Physoglenidae Physoglenidae is a family of araneomorph spiders first described by Alexander Petrunkevitch in 1928 as a subfamily of Pholcidae. It was later moved to Synotaxidae until a study in 2016 showed that they formed a distinct clade. Genera , the Worl ...

Pimoidae Pimoidae is a small family of araneomorph spiders first described by Jörg Wunderlich in 1986. As re-circumscribed in 2021, it is monophyletic, and contained 86 species in two genera. It is closely related to the Linyphiidae, and is sometimes ...

Symphytognathidae Symphytognathidae is a family of spiders with 90 described species in eight genera. They occur in the tropics of Central and South America and the Australian region (with Oceania). Exceptions include ''Anapistula benoiti'', '' Anapistula caecula ...

Synaphridae Synaphridae is a family of spiders with thirteen described species in three genera. It was first described as a subfamily of Anapidae, but it has since been raised to family status. Genera , the World Spider Catalog The World Spider Catalog ( ...

Synotaxidae Synotaxidae is a family of spiders with thirty-four described species in five genera. It was first described by Eugène Simon in 1895. Genera , the World Spider Catalog The World Spider Catalog (WSC) is an online searchable database concerned ...

Tetragnathidae Long-jawed orb weavers or long jawed spiders (Tetragnathidae) are a family of araneomorph spiders first described by Anton Menge in 1866. They have elongated bodies, legs, and chelicerae, and build small orb webs with an open hub with few, wide-s ...

Theridiidae Theridiidae, also known as the tangle-web spiders, cobweb spiders and comb-footed spiders, is a large family of Araneomorphae, araneomorph spiders first described by Carl Jakob Sundevall in 1833. This diverse, globally distributed family includes ...

Theridiosomatidae Theridiosomatidae, commonly known as ray spiders, are a family of araneomorph spiders first described by Eugène Simon in 1881. The family includes 137 species divided between 20 genera. They are most recognizable for their construction of cone-sha ...

Extinct families

After Dunlop et al. 2013 and Magalhaes et al. 2020 *† Baltsuccinidae * † Burmascutidae * † Cretamysmenidae * † Juraraneidae * † Leviunguidae * † Praetheridiidae * † Protheridiidae * † Pumiliopimoidae * † Zarqaraneidae

References

{{Taxonbar, from=Q774956 Araneomorphae Arachnid superfamilies