Spider taxonomy is the alpha taxonomy of the spiders, members of the Araneae order of the arthropod class Arachnida with about 40,000 described species. Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " Arachnids are a class ( Arachnida) of joint-legged Invertebrate Animals in the subphylum Chelicerata. Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings Carl Alexander Clerck ( 1709 - 22 July 1765) was a Swedish Entomologist and arachnologist. Year 1757 ( MDCCLVII) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod Taxonomy, sometimes alpha taxonomy, is the Science of finding describing and categorising Organisms thus giving rise to taxonomic groups or taxa Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings This article is about the taxonomic rank for the sequence of species in a taxonomic list see Taxonomic order In scientific classification used Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " A class is the Taxonomic rank in the Biological classification of organisms in Biology below phylum and above order. Arachnids are a class ( Arachnida) of joint-legged Invertebrate Animals in the subphylum Chelicerata. However there are likely many species that have escaped the human eye to this day, and many specimens stored in collections waiting to be described and classified. Specimen are a British band formed in the 1980s Their music has been described as being comprised of many different genres of music including Glam, Goth A Museum is distinguished by a collection of often unique objects that forms the core of its activities for exhibitions Education, Research It is estimated that only one third to one fifth of existing species have been described.

Arachnology currently divides spiders into three suborders with about 38 superfamilies, and 111 families. Arachnology (from Greek grc ἀράχνη arachnē, "spider" and grc -λογία -logia) is the scientific study of Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings Taxonomic rank ( rank, category, taxonomic category is an abstract term used in the Scientific classification, or Taxonomy, of organisms Taxonomic rank ( rank, category, taxonomic category is an abstract term used in the Scientific classification, or Taxonomy, of organisms In Biological classification, family ( Latin Seven of the 111 families are incertae sedis, meaning that their placement into superfamilies is not agreed upon; several other families are not placed in any superfamily. Incertae sedis ( Latin for "of uncertain placement" abbreviated "inc

Due to constant research, with new species being discovered every month and others being recognized as synonyms, the number of species in the families is bound to change and can never reflect the present status with total accuracy. In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon. Nevertheless, the species numbers given here are useful as a guideline.

See a table of Araneae families at the end of the article with some genera and species listed for each family (only identified species are included). Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank.

Suborder Mesothelae

Digitally enhanced image of a Sphodros rufipes that shows the nearly perfectly vertical orientation of the chelicerae, a prime characteristic of the Mygalomorphae.

Mesothelae resemble the Solifugae ("wind scorpions" or "sun scorpions") in having segmented plates on their abdomens that create the appearance of the segmented abdomens of these other arachnids. The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant Solifugae is an order of Arachnida containing more than 1000 described Species in about 140 genera. They are both few in number and also limited in geographical range.

• Arthrolycosidae (primitive spiders)
• Arthromygalidae (primitive spiders)
• Liphistiidae (primitive burrowing spiders)

Suborder Opisthothelae

Suborder Opisthothelae contains the spiders that have no plates on their abdomens. Arthrolycosidae is an extinct family of primitive Spiders that supposedly bear some resemblance to the Wolf spiders The Arthromygalidae are primitive fossil spiders that supposedly bear some resemblance to the Tarantulas The spider family Liphistiidae comprises 5 genera and 85 Species from Southeast Asia, China, and Japan. Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings It can be somewhat difficult on casual inspection to determine whether the chelicerae of members are of the sort that would put them into the infraorder of the mygalomorphs or the infraorder of the Araneomorphs. The spiders that are called "tarantulas" in English are so large and hairy that inspection of their chelicerae is hardly necessary to categorize one of them as a Mygalomorph. Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species Other, smaller, members of this suborder, however, look little different from the Araneomorphs. (See the picture of the Sphodros rufipes below. ) Many Araneomorphs are immediately identifiable as such since they are found on webs designed for the capture of prey or exhibit other habitat choices that eliminate the possibility that they could by Mygalomorphs.

Infraorder Mygalomorphae

Digitally modified photograph showing "chopsticks" orientation of the chelicerae of the Araneomorphae.

Spiders in infraorder Mygalomorphae are characterized by the vertical orientation of their chelicerae and the possession of four book lungs. The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which

Infraorder Araneomorphae

Most, if not all, of the spiders one encounters in everyday life belong to infraorder Araneomorphae. The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action It includes a wide range from the spiders that weave their beautiful orb webs in the garden, the more chaotic-looking webs of the cobweb spiders that frequent window frames and the corners of rooms, the crab spiders that lurk waiting for nectar- and pollen-gathering insects on flowers, to the jumping spiders that patrol the outside walls of a dwelling, and so on. They are characterized by having chelicerae whole tips approach each other as they bite, and (usually) having one pair of book lungs. The Chelicerae are mouth parts of the Chelicerata, an Arthropod Subphylum that includes Arachnids, Merostomata

Some important spider families are :-

• Pholcidae (daddy long-legs spiders)

These spiders are frequently seen in cellars. The Pholcidae are a Spider family in the suborder Araneomorphae. When light contact disturbs their web their characteristic response is to set the entire web moving the way a person would jump up and down on a trampoline. It is unclear why they cause their webs to vibrate in this way; moving their webs back and forward may increase the possibility that insects flying close by may be ensnared.

• Plectreuridae (plectreurid spiders)

Megaphobema robusta, one of the many kinds of spiders called "Tarantulas"

• Salticidae (jumping spiders)

The family of Araneae commonly called jumping spiders have a characteristic cephalothorax shapes, as shown in the diagram below. Plectreurid spiders (family Plectreuridae) belong to a small family confined to the North American Deserts and the island of Cuba. Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species The jumping spider family ( Salticidae) contains more than 500 described genera and over 5000 Species, making it the largest family of Spiders with about They have eight eyes, two of the very prominent, and excellent vision. Their maximum size is perhaps 13/16 inch (20 mm), but many species are much smaller than that. The largest North American species such as Phidippus regius, P. octopunctatis, etc. , are so heavy bodied that they cannot jump far. The smaller species of jumping spider can jump many times their own body length. They hunt by first getting within range of a prey animal such as a fly, securing a silken "climbing rope" to their current perch, and then jumping onto their prey and biting it. Many seem to take unerring aim at the neck of their prey. Should they jump from one twig to another in an attempt to capture prey and miss or get knocked off the second twig by their struggling prey then they are protected from falling by their silken lifeline. At night these spiders usually retreat to a silken "puptent" that they construct for their own protection and, when needed, as a place to deposit their eggs. They are frequently seen in sunlit areas on walls, tree trunks, and other such vertical surfaces. They are perhaps the only family of spiders who will take cognizance of a human in their general area and then turn their bodies and elevate their cephalothoraxes to keep the human under observation. If approached closely, e. g. , with the lens of a camera, some of them may choose to jump onto the nearby object to explore it. This behavior may be alarming but it never seems to be aggressive since these spiders are unwilling to attack prey that are very much larger than they are.

"Squared-off" cephalothorax of the jumping spiders.

Eye pattern of the jumping spiders.

Table of Families

Families listed in boldface contain one or more species which are believed to be venomous to humans. '''Spiders''' occasionally bite humans Although 98-99% of spider bites are harmless more rarely the symptoms of their bites can include necrotic wounds systemic

Sources:

• The World Spider Catalog, Version 8.0 (families, species count)
• Synopsis of the described Araneae of the World (suborders)

See also

References

• Reiskind, J. (1965). The Taxonomic Problem of Sexual Dimorphism in Spiders and a Synonymy in Myrmecotypus (Araneae, Clubionidae). Psyche 72:279-281 PDF

External links

• Abbreviations for Insect and Spider Collections of the World
• International Commission on Zoological Nomenclature

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