Spider silk is a protein fibre spun by spiders. Spiders use their silk to make webs or other structures, which function as sticky nets to catch other animals, or as nests or cocoons to protect their offspring, or to wrap up prey. They can also use their silk to suspend themselves, to float through the air, or to glide away from predators. Most spiders vary the thickness and stickiness of their silk for different uses.
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 forest. "Orb" can in English mean "circular", hence the English name of the group. Araneids have eight similar eyes, hairy or spiny legs, and no stridulating organs.
Amaurobiidae is a family of three-clawed cribellate or ecribellate spiders found in crevices and hollows or under stones where they build retreats, and are often collected in pitfall traps. Unlidded burrows are sometimes quite obvious in crusty, loamy soil. They are difficult to distinguish from related spiders in other families, especially Agelenidae, Desidae and Amphinectidae. Their intra- and interfamilial relationships are contentious. According to the World Spider Catalog, 2019, the family Amaurobiidae includes about 275 species in 49 genera.
Cribellum literally means "little sieve", and in biology the term generally applies to anatomical structures in the form of tiny perforated plates.
The Deinopoidea or deinopoids are group of cribellate araneomorph spiders that may be treated as a superfamily. As usually circumscribed, the group contains two families: Deinopidae and Uloboridae.
The anatomy of spiders includes many characteristics shared with other arachnids. These characteristics include bodies divided into two tagmata, eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed.
Ancylometes is a genus of Central and South American semiaquatic wandering spiders first described by Philipp Bertkau in 1880. Originally placed with the nursery web spiders, it was moved to the Ctenidae in 1967. The genus name is derived in part from Ancient Greek "ἀγκύλος" (ancylo-), meaning "crooked, bent".
Uloborus plumipes is a species of Old World cribellate spider in the family Uloboridae. Common names include the feather-legged lace weaver and the garden centre spider, the latter name being due to its frequent occurrence of this spider in garden centres on the world. The species name is derived from the Latin pluma "feather" and pes "foot".
Maevia inclemens is a relatively common and colorful jumping spider of North America. In the males there are two forms, a very rare phenomenon in zoology. These use different courting displays, and differ in appearance: the "tufted" morph has a black body and pedipalps ("palps"), three black tufts across its "head", and pale legs; and the "gray" morph has black and white stripes all over its body and legs, orange palps, and no tufts. However, each form accounts for 50% of the adult males, and they are equally successful in mating. A female of Maevia inclemens is 6.5 to 8.0 millimetres long, while males are 4.75 to 6.50 millimetres long.
Tarantulas comprise a group of large and often ″hairy″ spiders of the family Theraphosidae. Currently, about 1,000 species have been identified. The term tarantula is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder (Mygalomorphae) are commonly referred to as "tarantulas" or "false tarantulas". Some of the more common species have become popular in the exotic pet trade. Many New World species kept as pets have urticating hairs that can cause irritation to the skin, and in extreme cases, cause damage to the eyes.
A spider web, spiderweb, spider's web, or cobweb is a structure created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey.
Pholcus phalangioides, commonly known as daddy long-legs spider or long-bodied cellar spider, is a spider of the family Pholcidae. It is also known as the skull spider due its cephalothorax resembling a human skull. This is the only spider species described by the Swiss entomologist Johann Kaspar Füssli, who first recorded it in 1775. Its common name of "daddy long-legs" should not be confused with a different arachnid species with the same common name, the harvestman (Opiliones).
Eoplectreurys is an extinct monotypic genus of spider from the family Plectreuridae, with a sole species, Eoplectreurys gertschi. The fossils of Eoplectreurys were recovered from the ~164 Ma old Middle Jurassic Daohugou formation tuffs in Inner Mongolia, China.
Spiders are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitat with the exceptions of air and sea colonization. As of July 2019, at least 48,200 spider species, and 120 families have been recorded by taxonomists. However, there has been dissension within the scientific community as to how all these families should be classified, as evidenced by the over 20 different classifications that have been proposed since 1900.
This glossary describes the terms used in formal descriptions of spiders; where applicable these terms are used in describing other arachnids.
Mongolarachne is an extinct genus of spiders placed in the monogeneric family Mongolarachnidae. The genus contains only one species, Mongolarachne jurassica, described in 2013, which is presently the largest fossilized spider on record. The type species was originally described as Nephila jurassica and placed in the living genus Nephila which contains the golden silk orb-weavers.
Progradungula otwayensis, commonly known as the odd-clawed spider, is a species of cribellate spider endemic to the Great Otway National Park of Victoria, Australia. It is one of only two species in the gradungulid genus Progradungula.
Hypochilus thorelli is a species of spider in the family Hypochilidae. Unlike almost all other araneomorph or "true" spiders, members of the family have four book lungs. They are often called "lampshade spiders" because of the shape of their webs which are usually built underneath ledges or projections. H. thorelli is found in the southern Appalachian Mountains of the eastern United States.
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 group is not monophyletic. The issue relates to the origin of orb webs: whether they evolved early in the evolutionary history of 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. As of September 2018, 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.
Gelotia lanka is a species of spider of the genus Gelotia. It is endemic to Sri Lanka.
