The Deinopoidea or deinopoids are group of
cribellate
Cribellum literally means "little sieve", and in biology the term generally applies to anatomical structures in the form of tiny perforated plates.
In certain groups of diatoms it refers to microscopically punctured regions of the frustule, or o ...
araneomorph
The Araneomorphae (also called the Labidognatha) 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 (tarantulas and their ...
spiders that may be treated as a
superfamily.
[ As usually ]circumscribed
In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius.
Not every polyg ...
, the group contains two families
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...
: Deinopidae
Deinopidae, also known as net casting spiders, is a family of cribellate spiders first described by Carl Ludwig Koch in 1850. It consists of stick-like elongated spiders that catch prey by stretching a web across their front legs before propelling ...
and Uloboridae
Uloboridae is a family of non-venomous spiders, known as cribellate orb weavers or hackled orb weavers. Their lack of venom glands is a secondarily evolved trait. Instead, they wrap their prey thoroughly in silk, cover it in regurgitated digestive ...
.[
Some studies have produced ]cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...
s in which the Deinopoidea are paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...
.[ A review in 2014 concluded that "at this time the monophyly of Deinopoidea remains dubious".][
]
Characteristics
The group is characterized by the production of orb webs with catching threads of cribellate silk (i.e. silk made up of very fine threads produced by combing an initial thread using the spider's calamistrum In spiders, the calamistrum is a row of specialized leg bristles used to comb out fine bands of silk. It is only found on cribellate spiders, that is, spiders that possess the spinning organ known as the cribellum. The calamistrum and cribellum ar ...
). Uloborids spin vertical orb webs, very similar in shape to those made by araneids, such as the cross spider. Deinopids initially spin an orb web, which they then suspend between their front legs and use as a net to ensnare prey.[
]
Phylogeny
According to one hypothesis, the two groups in which orb-weaving occurs, the cribellate
Cribellum literally means "little sieve", and in biology the term generally applies to anatomical structures in the form of tiny perforated plates.
In certain groups of diatoms it refers to microscopically punctured regions of the frustule, or o ...
deinopoids and the ecribellate araneoids, make up a single monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...
group, Orbiculariae
Orbiculariae is a potential clade of araneomorph spiders, uniting two groups that make orb webs. Phylogenetic analyses based on morphological characters have generally recovered this clade; analyses based on DNA have regularly concluded that the ...
, in which orb-weaving evolved. One hypothesis for the relationships involved is summarized in the cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...
below.[
An alternative view is that both the Deinopoidea and the Orbiculariae are ]paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...
(i.e. do not form a good taxa). Another hypothesis for the phylogeny of the Entelegynae is shown below (parentheses show the genera included in the study).
References
{{Taxonbar, from=Q54921
Araneomorphae
Arachnid superfamilies