The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to their creation of trapdoors over their burrows. Other prominent groups include Australian funnel web spiders and tarantulas, with the latter accounting for around one third of all mygalomorphs.
Huntsman spiders, members of the family Sparassidae, are known by this name because of their speed and mode of hunting. They are also called giant crab spiders because of their size and appearance. Larger species sometimes are referred to as wood spiders, because of their preference for woody places. In southern Africa the genus Palystes are known as rain spiders or lizard-eating spiders. Commonly, they are confused with baboon spiders from the Mygalomorphae infraorder, which are not closely related.
Nursery web spiders (Pisauridae) is a family of araneomorph spiders first described by Eugène Simon in 1890. They resemble wolf spiders (Lycosidae) except for several key differences. Wolf spiders have two very prominent eyes in addition to the other six, while a nursery web spider's eyes are all about the same size. Additionally, female nursery web spiders carry their egg sacs with their jaws and pedipalps instead of attaching them to their spinnerets as wolf spiders do. When the eggs are about to hatch, a female spider builds a nursery "tent", places her egg sac inside, and stands guard outside, hence the family's common name. Like the wolf spiders, however, the nursery web spiders are roaming hunters that don't use webs for catching prey.
Ctenizidae is a small family of mygalomorph spiders that construct burrows with a cork-like trapdoor made of soil, vegetation, and silk. They may be called trapdoor spiders, as are other, similar species, such as those of the families Liphistiidae, Barychelidae, and Cyrtaucheniidae, and some species in the Idiopidae and Nemesiidae. The name comes from the distinctive behavior of the spiders to construct trapdoors, and ambush prey from beneath them.
Sicariidae is a family of six-eyed venomous spiders known for their potentially necrotic bites. The family consists of three genera and about 160 species. Well known spiders in this family include the brown recluse spider and the six-eyed sand spider.
The Pholcidae are a family of araneomorph spiders. The family contains more than 1,800 individual species of pholcids, including those commonly known as cellar spider, daddy long-legs spider, carpenter spider, daddy long-legger, vibrating spider, gyrating spider, long daddy, and skull spider. The family, first described by Carl Ludwig Koch in 1850, is divided into 94 genera.
The sac spiders of the family Clubionidae have a very confusing taxonomic history. Once, this family was a large catch-all taxon for a disparate collection of spiders, similar only in that they had eight eyes arranged in two rows and conical anterior spinnerets that touched, and were wandering predators that built silken retreats, or sacs, usually on plant terminals, between leaves, under bark, or under rocks. These are now recognized to include several families, some of which are more closely related to the three-clawed spiders, like lynx and wolf spiders, than to Clubionidae and related families.
Selenopidae, also called wall crab spiders, wall spiders and flatties, is a family of araneomorph spiders first described by Eugène Simon in 1897. It contains over 280 species in nine genera, of which Selenops is the most well-known. This family is just one of several families whose English name includes the phrase "crab spider". These spiders are often called "Flatties" due to their flattened dorsal profile. The Afrikaans name for these spiders is "Muurspinnekop."
The Goliath birdeater belongs to the tarantula family Theraphosidae. Found in northern South America, it is the largest spider in the world by mass and body length, and second to the giant huntsman spider by leg span. It is also called the Goliath tarantula or Goliath bird-eating spider; the practice of calling theraphosids "bird-eating" derives from an early 18th-century copper engraving by Maria Sibylla Merian that shows one eating a hummingbird. Despite the spider's name, it rarely preys on birds.
Scaffold web spiders or cave cobweb spiders (Nesticidae) are a family of araneomorph spiders closely allied with tangle-web spiders (Theridiidae). Like the Theridiidae, these spiders have a comb of serrated bristles on the hind tarsi that are used to pull silk bands from the spinnerets. Nesticidae contains 16 genera and about 300 species, many of which are associated with caves or overhangs. The genus Nesticus is the type for the family and is found throughout the world. The related Eidmannella has speciated considerably in Texas caves and includes some extremely localized species that are considered threatened. One species, Eidmannella pallida, is found in caves and under overhangs, but also in agricultural fields and other habitats away from such restricted areas. The genus Carpathonesticus is found in central Eurasia.
Theridiosomatidae, commonly known as Ray Spiders, are a family of Arachnid first described by Eugène Simon in 1881. The family includes 137 species divided between 20 genus. They are most recognizable for their construction of cone-shaped webs.
Actinopodidae is a family of mygalomorph orb weaver spiders found in mainland Australia and South America usually in open forest. Species are most common in Queensland, Australia. It includes mouse spiders, whose bites, though rare, are considered medically significant and potentially dangerous.
Idiopidae, also known as armored trapdoor spiders, is a family of mygalomorph spiders first described by Eugène Simon in 1889. They have a large body similar to tarantulas.
Cithaeronidae is a small family of araneomorph spiders first described by Simon in 1893 Female Cithaeron are about 5 to 7 millimetres long, males about 4 millimetres (0.16 in).
Mysmenidae is a spider family with about 135 described species in thirteen genera. The family is one of the least well known of the orb-weaving spiders because of their small size and cryptic behaviour. These spiders are found in humid habitats such as among leaf litter and in caves.
Inthaeron is a monotypic genus of Asian araneomorph spiders in the family Cithaeronidae, containing the single species, Inthaeron rossi. It was first described by Norman I. Platnick in 1991, and has only been found in India. Females can be distinguished from those of its sister genus, Cithaeron, by the arrangement of cylindrical gland spigots on the posterior median spinnerets, appearing in two rows rather than in clusters. The name is derived from "India", the country it was first found in, and "Cithaeron", the name of the other genus of Cithaeronidae.
Baryphyma trifrons is a species of dwarf spider in the family Linyphiidae. It is found in North America, Europe, the Caucasus, and in a range from Russian Europe to the Far East).
Psilochorus simoni is a species of cellar spider in the family Pholcidae. It is found in the United States, and has been introduced into Europe, Turkey, and New Zealand.
Cithaeron is a genus of araneomorph spiders in the family Cithaeronidae, first described by O. Pickard-Cambridge in 1872.
Micaria pasadena is a species of ground spider in the family Gnaphosidae. It is found in the United States and Mexico.
