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Deinopoidea
The Deinopoidea or deinopoids are group of cribellate Araneomorphae, araneomorph spiders that may be treated as a Taxonomic rank, superfamily. As usually Circumscription (taxonomy), circumscribed, the group contains two family (biology), families: Deinopidae and Uloboridae. Some studies have produced cladograms in which the Deinopoidea are Paraphyly, paraphyletic. 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). Uloborids spin vertical orb webs, very similar in shape to those made by araneids, such as the Araneus diadematus, 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 wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbiculariae
Orbiculariae is a potential clade of Araneomorphae, araneomorph spiders, uniting two groups that make orb webs. Phylogenetics, Phylogenetic analyses based on morphological characters have generally recovered this clade; analyses based on DNA have regularly concluded that the group is not monophyletic. The issue relates to the origin of orb webs: whether they evolved early in the evolutionary history of Entelegynae, entelegyne spiders, with many groups subsequently losing the ability to make orb webs, or whether they evolved later, with fewer groups having lost this ability. , the weight of the evidence strongly favours the non-monophyly of "Orbiculariae" and hence the early evolution of orb webs, followed by multiple changes and losses. History Whether spiders that weave true orb webs form a coherent group, and so should be classified together, is a question that has a long history. Two groups of spiders that spin orb webs are the Uloboridae and the Araneidae. Although their web ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 outer layer. In certain groups of spider species, so-called cribellate spiders, the cribellum is a silk spinning organ. Unlike the usual spinnerets of spiders, the cribellum consists of one or more plates covered in thousands of tiny spigots, tiny holes that hardly project from the surface, in contrast to the elongated spigots that project from spinnerets. These minute spigots produce extremely fine fibers, merely tens of nanometres thick, which are combed out by the spider's calamistrum, producing silk with a woolly texture. The fibers are so small in diameter that they are strongly subject to Van der Waals forces. In addition, the fibres have a surface that absorbs waxes from the epicuticle of insect prey on contact. This creates a po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eresoidea
The Eresoidea or eresoids are a group of araneomorph spiders that have been treated as a superfamily. As usually circumscribed, the group contains three families: Eresidae, Hersiliidae and Oecobiidae. Studies and reviews based on morphology suggested the monophyly of the group; more recent gene-based studies have found the Eresidae and Oecobiidae to fall into different clades, placing doubt on the acceptability of the taxon. Some researchers have grouped Hersiliidae and Oecobiidae into the separate superfamily Oecobioidea, a conclusion supported in a 2017 study, which does not support Eresoidea. Phylogeny Some largely morphology-based phylogenetic studies that included the three families assigned to the Eresoidea supported their monophyly, with the internal structure of the clade being as shown below. Eresoidea was placed as basal in the Entelegynae, with its precise position relative to the Palpimanoidea, also basal, varying. In 2015, Jonathan A. Coddington summarized this a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oecobiidae
Oecobiidae, also called disc web spiders, is a family of araneomorph spiders, including about 100 described species. They are small to moderate sized spiders (about long combined head and body length, depending on the species. Larger ones tend to be desert-dwelling. The legs are unusually evenly placed around the prosoma; most other spiders have some legs directed clearly forward and the rest clearly backward, or all forward. The first two pairs of legs of many Oecobiids point forward then curve backwards; somehow in a running spider this gives a curiously scurrying, wheel-like impression that is characteristic of many Oecobiidae, and is helpful as a rough-and-ready aid to identification in the field. Characteristic of the family is the anal gland; it bears a tuft of long hairs. Typical colour patterns range from dark-patterned cream in some smaller species, to a small number of symmetrically-placed, conspicuous round light spots (commonly yellow or white) on a background that ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deinopis
''Deinopis'', also known as net-casting spiders, gladiator spiders and ogre-faced spiders, is a genus of net-casting spiders that was first described by W. S. MacLeay in 1839. Its distribution is widely tropical and subtropical. They catch their prey using a specially spun "net". The name is derived from the Greek (''deinos''), meaning "fearful", and ''opis'', meaning "appearance", referring to their ogre-like faces. The spelling "''Dinopis''" is also found, but is regarded as an "unjustified emendation". Net-casting Spiders in the genus ''Deinopis'' catch their prey in an unusual fashion. They first spin a small upright rectangular cribellate web. This is then detached from its supporting threads and held horizontally above the ground by the spider's long front two pairs of legs while the spider hangs almost vertically. Passing prey is then captured by dropping the "net" over it. Eyes The two posterior median eyes are enlarged and forward-facing. These eyes have a wide field ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philoponella
''Philoponella'' is a genus of uloborid spiders. Like all Uloboridae, these species have no venom. Cooperation Some species (among them ''P. congregabilis'' and ''P. oweni'') construct communal webs, but nevertheless do not capture prey cooperatively. However, a few species, such as ''P. raffrayi'', are known to cooperate in prey capture. A colony of ''P. raffrayi'' is composed of individual orb-webs connected by non-adhesive silk. Its average body length is about 6 mm in females and 3 mm in males. Adult females are orange for at least a week after the final molt, and become black a few weeks later. In these colonies, ''Argyrodes'' and '' Portia'' species can also be found, acting as kleptoparasites and predators, respectively. When relatively large prey is trapped on the periphery of the colony, two females cooperate in about 10% of cases in wrapping it, which increases their chances of success about fourfold. However, only one female then feeds on this prey. Cooperat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodyphus
''Stegodyphus'' is a genus of velvet spiders that was first described by Eugène Simon in 1873. They are distributed from Africa to Europe and Asia, with one species (''S. manaus'') found in Brazil. The name is derived from Ancient Greek ('' stegos''), meaning "covered". At least three species are social spiders, and several are known to use ballooning as a method of dispersal. Species it contains twenty species: *'' Stegodyphus africanus'' ( Blackwall, 1866) – Africa *'' Stegodyphus bicolor'' (O. Pickard-Cambridge, 1869) – Southern Africa *'' Stegodyphus dufouri'' ( Audouin, 1826) – North, West Africa *''Stegodyphus dumicola'' Pocock, 1898 – Central, Southern Africa *'' Stegodyphus hildebrandti'' ( Karsch, 1878) – Central, East Africa, Zanzibar *'' Stegodyphus hisarensis'' Arora & Monga, 1992 – India *''Stegodyphus lineatus'' (Latreille, 1817) ( type) – Southern Europe, North Africa to Tajikistan *'' Stegodyphus lineifrons'' Pocock, 1898 – East Africa *'' Ste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eresidae
Velvet spiders (family Eresidae) are a small group (about 130 species in 9 genera) of spiders almost entirely limited to the Old World, with exception of a few species known from Brazil. In Europe some are commonly called the ladybird spiders Description This family can sometimes be confused with the jumping spiders, or those in the Palpimanidae family. These spiders are usually black or brown in color, thought they can also have brighter colors as pictured. As their common name implies they can look quite smooth and velvety. They usually live in silken tubes under objects, or underground, but the genus '' Stegodyphus,'' builds silken nests. Identification They can be distinguished from most species except the Penestomidae by their semi rectangular carapace and clypeal hood. Thought the can be distinguished from Penestomidae by the eye arrangement, straight anterior eye row and strongly recurved posterior eye row, with the median eyes close together. Social Behavior Som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RTA Clade
The RTA clade is a clade of araneomorph spiders, united by the possession of a retrolateral tibial apophysis – a backward-facing projection on the tibia of the male pedipalp. The clade contains over 21,000 species, almost half the current total of about 46,000 known species of spider. Most of the members of the clade are wanderers and do not build webs. Despite making up approximately half of all modern spider diversity, there are no unambiguous records of the group from the Mesozoic and molecular clock evidence suggests that the group began to diversify during the Late Cretaceous. Families In 2005, Coddington included 39 families in a cladogram showing the RTA clade: *Agelenidae *Amaurobiidae *Ammoxenidae *Amphinectidae (paraphyletic; merged into Desidae) *Anyphaenidae *Cithaeronidae *Clubionidae *Corinnidae * Cryptothelidae *Ctenidae *Desidae *Dictynidae * Gallieniellidae *Gnaphosidae *Lamponidae * Liocranidae *Lycosidae *Miturgidae (paraphyletic) * Oxyopidae *Philodromidae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicodamidae
Nicodamidae is a family of araneomorph spiders with about thirty species in seven genera. They are small to medium-sized spiders found near the ground of eucalypt forest in small sheet webs. The species of this family are only present in Australia and Papua New Guinea. In most cases the cephalothorax and legs are uniformly red and the abdomen black, for which these species are sometimes called the "red and black spiders". Taxonomy The family Nicodamidae was established by Eugène Simon in 1897 for his newly described species ''Nicodamus dimidiatus'' (now '' Dimidamus dimidiatus''). Mark Harvey published a major review of the family in 1995. At the time of the review, only two genera were accepted, '' Nicodamus'' from Australia and New Guinea, and ''Megadictyna'' from New Zealand. Based on a morphological cladistic analysis, Harvey divided the family into two subfamilies, Nicodaminae and Megadictyninae, and erected seven new genera. In 1967, Pekka T. Lehtinen proposed that Megadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araneoidea
Araneoidea is a taxon of araneomorph spiders, termed "araneoids", treated as a superfamily. As with many such groups, its circumscription has varied; in particular some families that had at one time moved to the Palpimanoidea 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 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 Palpimanoidea. In 1984, Raymond R. Forster and Norman I. Platnick 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 famili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
