Dionycha
Encyclopedia
The Dionycha are a phylogenetic group of spiders (Araneomorphae
:Entelegynae
) with about 10,000 species. 17 families belong to this group, amongst others: Salticidae (jumping spiders), Gnaphosoidea
, Thomisidae (crab spiders), and the Clubionidae. Spiders in this group have better senses (sight, hearing) than others, some even show courtship dances and songs.
The Dionycha probably evolved from the web-building Trionycha. Unlike these, the Dionycha have only two instead of three tarsal claws. The central third claw of the Trionycha is responsible for tracking the silk
thread. Instead of this claw, Dionycha have dense tufts of scupula hairs that produce strong adhesion, enabling some species to climb glass. Most species hunt their prey instead of building webs, although some species of Trionycha (members of Lycosoidea
) also hunt.
There are no cribellate members in the Dionycha.
The monophyly
of the Dionycha has been disputed. Today it is thought that the reduction of the third claw evolved several times independently.
Araneomorphae
The Araneomorphae are a suborder of spiders. They are distinguished by having fangs that oppose each other and cross in a pinching action, in contrast to the Mygalomorphae , which have fangs that are nearly parallel in alignment.- Distinguishing characteristics :Note the difference in the...
:Entelegynae
Entelegynae
The Entelegynae are a subgroup of araneomorph spiders. Almost all members of this group, unlike most members of Haplogynae, have eight eyes, and females have a genital plate....
) with about 10,000 species. 17 families belong to this group, amongst others: Salticidae (jumping spiders), Gnaphosoidea
Gnaphosoidea
The Gnaphosoidea are a superfamily of araneomorph, mostly eight-eyed spiders, with seven families:* Ammoxenidae* Cithaeronidae * Gallieniellidae* Gnaphosidae* Lamponidae* Prodidomidae* Trochanteriidae...
, Thomisidae (crab spiders), and the Clubionidae. Spiders in this group have better senses (sight, hearing) than others, some even show courtship dances and songs.
The Dionycha probably evolved from the web-building Trionycha. Unlike these, the Dionycha have only two instead of three tarsal claws. The central third claw of the Trionycha is responsible for tracking the silk
Spider silk
Spider silk is a protein fiber spun by spiders. Spiders use their silk to make webs or other structures, which function as nets to catch other animals, or as nests or cocoons for protection for their offspring...
thread. Instead of this claw, Dionycha have dense tufts of scupula hairs that produce strong adhesion, enabling some species to climb glass. Most species hunt their prey instead of building webs, although some species of Trionycha (members of Lycosoidea
Lycosoidea
The Lycosoidea are a superfamily of araneomorph eight-eyed spiders, with twelve families:* Ctenidae* Lycosidae* Neolanidae* Oxyopidae* Pisauridae* Psechridae* Senoculidae* Stiphidiidae* Trechaleidae* Zoridae* Zorocratidae* Zoropsidae...
) also hunt.
There are no cribellate members in the Dionycha.
The monophyly
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
of the Dionycha has been disputed. Today it is thought that the reduction of the third claw evolved several times independently.