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The Araneomorphae (also called the Labidognatha or "true spiders") are an
infraorder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classific ...
of
spider Spiders (order (biology), order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude spider silk, silk. They are the largest order of arachnids and ran ...
s. They are distinguishable by
chelicerae The chelicerae () are the arthropod mouthparts, mouthparts of the subphylum Chelicerata, an arthropod group that includes arachnids, horseshoe crabs, and sea spiders. Commonly referred to as "jaws", chelicerae may be shaped as either articulated ...
(fangs) that point diagonally forward and cross in a pinching action, in contrast to the
Mygalomorphae The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3,000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to t ...
(tarantulas and their close kin), where they point straight down. Araneomorphs comprise the vast majority (about 93%) of living spiders.


Distinguishing characteristics

Most spider species are Araneomorphae, which have
fangs A fang is a long, pointed tooth. In mammals, a fang is a modified maxillary tooth, used for biting and tearing flesh. In snakes, it is a specialized tooth that is associated with a venom gland (see snake venom). Spiders also have external Chelic ...
that face towards each other, increasing the orientations that they can employ during prey-capture. They have fewer book lungs (when present) – usually one pair – and the females typically live one year. The Mygalomorphae have
fangs A fang is a long, pointed tooth. In mammals, a fang is a modified maxillary tooth, used for biting and tearing flesh. In snakes, it is a specialized tooth that is associated with a venom gland (see snake venom). Spiders also have external Chelic ...
that face towards the ground, and which are parallel to the long axis of the spider's body, thus they have only one orientation they can employ during prey capture. They have two pairs of book lungs, and the females often live many years. Image:Cheiracanthium punctorium frei 1 17 Forst Jungfernhdeide Jg 46 070920.jpg, This '' Cheiracanthium punctorium'' shows the orientation of Araneomorphae fangs. Image:Atrax robustus.jpg, This '' Atrax robustus'' shows the orientation of Mygalomorphae fangs.


Spiders included

Almost all of the familiar spiders are included in the Araneomorphae group, one major exception being the
tarantula Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae. , 1,100 species have been identified, with 166 genera. The term "tarantula" is usually used to describe members of the family Theraphosidae, although ...
s. There are a few other Mygalomorphae species that live around homes or gardens, but they typically are relatively small and not easily noticed. The Araneomorphae, to the contrary, include the weavers of spiral webs; the cobweb spiders that live in the corners of rooms, and between windows and screens; the crab spiders that lurk on the surfaces of flowers in gardens; the jumping spiders that are visible hunting on surfaces; the
wolf spider Wolf spiders are members of the family Lycosidae (), named for their robust and agile hunting skills and excellent eyesight. They live mostly in solitude, hunt alone, and usually do not spin webs. Some are opportunistic hunters, pouncing upon ...
s that carpet hunting sites in sunny spots; and the large huntsman spiders.


Systematics

In older schemes, the Araneomorphae were divided into two lineages, the ''Hypochilae'' (containing only the family
Hypochilidae Lampshade spiders, family Hypochilidae, are among the most primitive of araneomorph spiders. There are two genus, genera and twelve species currently recognized. Like mygalomorphs, most hypochilids have two pairs of book lungs, but like araneomor ...
), and the ''Neocribellatae''. The Neocribellatae were in turn divided into the Austrochiloidea, and the two
series Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used i ...
Haplogynae and Entelogynae, each containing several superfamilies.
Molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...
studies have shown that the haplogynes in particular are not a
monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...
group. A 2020 study suggested the relationships among the major groups were as shown in the following cladogram. The blue bar to the right shows the former
Haplogynae The Haplogynae or haplogynes are one of the two main groups into which araneomorph spiders have traditionally been divided, the other being the Entelegynae. Morphological phylogenetic studies suggested that the Haplogynae formed a clade; more re ...
in the sense of Coddington (2005).


Table of families


Extinct families

* Pholcochyroceridae


Notes


References


Citations


External links

* * {{taxonbar, from1=Q12084