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47-540: Solifugae is an order of arachnids known variously as solifuges, sun spiders, camel spiders , and wind scorpions . The order includes more than 1,000 described species in about 147 genera . Despite the common names, they are neither true scorpions (order Scorpiones) nor true spiders (order Araneae ). Because of this, it's less ambiguous to call them "solifuges". Most species of solifuge live in dry climates and feed opportunistically on ground-dwelling arthropods and other small animals. The largest species grow to

94-461: A cohors (plural cohortes ). Some of the plant families still retain the names of Linnaean "natural orders" or even the names of pre-Linnaean natural groups recognized by Linnaeus as orders in his natural classification (e.g. Palmae or Labiatae ). Such names are known as descriptive family names. In the field of zoology , the Linnaean orders were used more consistently. That is,

141-501: A carapace, also called a prosomal dorsal shield or peltidium , which is composed of three distinct elements called propeltidium, mesopeltidium and metapeltidium. The propeltidium contains the eyes, the chelicerae that, in most species, are conspicuously large, the pedipalps and the first two pairs of legs. Meso- and metapeltidium contains the third and fourth pairs of legs. The chelicerae serve as jaws and in many species also are used for stridulation . Unlike scorpions, solifuges do not have

188-570: A distinct rank of biological classification having its own distinctive name (and not just called a higher genus ( genus summum )) was first introduced by the German botanist Augustus Quirinus Rivinus in his classification of plants that appeared in a series of treatises in the 1690s. Carl Linnaeus was the first to apply it consistently to the division of all three kingdoms of nature (then minerals , plants , and animals ) in his Systema Naturae (1735, 1st. Ed.). For plants, Linnaeus' orders in

235-529: A heart and respiratory organs. Like other arachnids outside the orders of scorpions and the Tetrapulmonata , the Solifugae lack book lungs , having instead a well-developed tracheal system that inhales and exhales air through a number of spiracles - one pair between the second and third pair of walking legs, two pairs on the abdomen on abdominal segments three and four, and an unpaired spiracle on

282-630: A length of 12–15 cm (5–6 in), including legs. A number of urban legends exaggerate the size and speed of solifuges, and their potential danger to humans, which is negligible. The order's name is derived from the Latin "sol" meaning "sun" and "fugere" meaning "to flee". Put together, it means "those who flee from the sun". These animals have a number of common names including sun spiders, wind scorpions, wind spiders, red romans, and camel spiders. In Afrikaans , they are known as "haarskeerders" ("hair cutters"), and "baardskeerders" ("beard cutters"). This

329-546: A name. Because of this, a later genomic study established three additional families: Dinorhaxidae , Lipophagidae , and Namibesiidae . Below is a family tree of the various solifuge families based on phylogenomics . Gylippidae Eremobatidae Karschiidae Galeodidae Rhagodidae Ceromidae Hexisopodidae Solpugidae Others Solifuges have been recognized as distinct taxa from ancient times. In Aelian 's De natura animalium , "four-jawed spiders" are credited, along with scorpions , as being responsible for

376-511: A rattling noise. These elements work the same way as in most other arachnids. Although the Solifugae appear to have five pairs of legs, only the hind four pairs are true legs. Each true leg has seven segments: coxa , trochanter , femur , patella , tibia , metatarsus , and tarsus . The first, or anterior, of the five pairs of leg-like appendages are not "actual" legs, but pedipalps , and they have only five segments each. The pedipalps of

423-455: A species of 5 cm (2.0 in) has been observed to eat more than 100 flies during that time in the laboratory. The Solifugae undergo a number of stages including, egg, postembryo, 9–10 nymphal instars, and adults. Solifuges are an order of arachnids comprising over 1200 species in 146 genera assigned to 16 different families . Solifuges can be divided into two groups of families which are recognized as distinct suborders . These are

470-405: A third tagma that forms a "tail". Currently, neither fossil nor embryological evidence shows that arachnids ever had a separate thorax-like division, so the validity of the term cephalothorax, which means a fused cephalon , or head, and thorax , has been questioned. Also, arguments exist against use of "abdomen", as the opisthosoma of many arachnids contains organs atypical of an abdomen, such as

517-456: A tree. This increases the surface area for gas exchange in the insect. Areas of intense metabolic activity, such as the digestive tract and flight muscles, have very dense aggregations of tracheoles. Though usually closely associated with cells, tracheoles physically penetrate only the flight muscle cells which have the highest oxygen demands. Unlike the larger tracheae which are derived of ectodermal stem cells, tracheoles do not molt with

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564-459: A year). Reproduction can involve direct or indirect sperm transfer; when indirect, the male emits a spermatophore on the ground and then inserts it with his chelicerae in the female's genital pore. To do this, he flings the female on her back. The female then digs a burrow, into which she lays 50 to 200 eggs; some species then guard them until they hatch. Because the female does not feed during this time, she tries to fatten herself beforehand, and

611-447: Is in reference to myths that they cut hair to be used as nest bedding. Solifuges are moderately small to large arachnids (a few millimeters to several centimeters in body length), with the larger species reaching 12–15 cm (5–6 in) in length, including legs. In practice, the respective lengths of the legs of various species differ greatly, so the resulting figures are often misleading. More practical measurements refer primarily to

658-489: Is long and narrow is held perpendicular to the chelicerae and chewed from one end to another. More round prey is chewed by rotating the body all at once. This chewing motion turns the food into a liquidized paste which is then swallowed by the animal's pharynx . Solifuges that haven't fed for long periods are known to eat faster than ones that fed recently. Larger solifuges are also known to eat faster than smaller ones. The Solifugae are typically univoltine (reproducing once

705-533: Is usually written with a capital letter. For some groups of organisms, their orders may follow consistent naming schemes . Orders of plants , fungi , and algae use the suffix -ales (e.g. Dictyotales ). Orders of birds and fishes use the Latin suffix -iformes meaning 'having the form of' (e.g. Passeriformes ), but orders of mammals and invertebrates are not so consistent (e.g. Artiodactyla , Actiniaria , Primates ). For some clades covered by

752-704: The Australosolifugae which live predominantly in the Southern Hemisphere and the Boreosolifugae which live mostly in the Northern Hemisphere . This phylogeny is considered congruent with a Gondwanan origin for Australosolifugae and a Laurasian origin for Boreosolifugae. When looking at their relationships, the families Ammotrechidae and Daesiidae were found to be paraphyletic , leading to multiple clades without

799-528: The International Code of Zoological Nomenclature , several additional classifications are sometimes used, although not all of these are officially recognized. In their 1997 classification of mammals , McKenna and Bell used two extra levels between superorder and order: grandorder and mirorder . Michael Novacek (1986) inserted them at the same position. Michael Benton (2005) inserted them between superorder and magnorder instead. This position

846-815: The Systema Naturae and the Species Plantarum were strictly artificial, introduced to subdivide the artificial classes into more comprehensible smaller groups. When the word ordo was first consistently used for natural units of plants, in 19th-century works such as the Prodromus Systematis Naturalis Regni Vegetabilis of Augustin Pyramus de Candolle and the Genera Plantarum of Bentham & Hooker, it indicated taxa that are now given

893-645: The chelicerae . The ocelli's lenses are usually atrophied. However, in some species both nerves and pigment cells are present. In species where lateral eyes are functional, they probably aid in detecting motions or changes in light intensity. Most solifuges live in tropics and subtropical deserts in the Americas , Southern Europe , Africa , the Middle East , and South Asia . Surprisingly, these animals are absent in Australia and Madagascar . Within

940-429: The limb's suction cups, then rapidly pulled towards the chelicerae to be chewed. These motions happen so fast that they can't be distinguished. Before eating, solifuges prepare their food by removing any parts they find unfavorable. In arthropods , these are typically areas that have a high amount of chitin ( heads , antennae , wings , etc). Solifuges eat in different ways based on the shape of their food. Prey that

987-400: The posterior three pairs. That smaller anterior pair acts largely in a sensory role as a supplement to the pedipalps, and in many species they accordingly lack tarsi. At the tips of their pedipalps, Solifugae bear a membranous suctorial organ, which are used for capturing prey, and also for bringing water to their mouthparts for drinking and climbing smooth surfaces. For the most part, only

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1034-419: The rhabdomeres beneath. Rhabdomeres are light-sensitive and function as the eye's photoreceptors . Interspersed between the rhabdomeres are pigment cells. The eye's optic nerve begins at its center and is connected to the axons of numerous rhabdomeres. In addition to the median eyes , solifuges possess a pair of vestigial lateral ocelli . These eyes are found in pits on the animal's cephalic lobes near

1081-537: The 10-segmented abdomen , or opisthosoma , is the posterior tagma. The abdominal tergites and sternites are separated by large areas of intersegmental membranes, giving it a high degree of flexibility and ability to stretch considerably, which allows it to consume a large amount of food. As shown in the illustrations, the solifuge prosoma and opisthosoma are not separated by nearly as clear a constriction and connecting tube or " pedicel " as occurs in Araneae. The lack of

1128-583: The Solifugae are their large chelicerae , which in many species are longer than the prosoma. Each of the two chelicerae has two articles (segments, parts connected by a joint), forming a powerful pincer, much like that of a crab; each article bears a variable number of teeth, largely depending on the species. The chelicerae of many species are surprisingly strong; they are capable of shearing hair or feathers from vertebrate prey or carrion, and of cutting through skin and thin bones such as those of small birds. Many Solifugae stridulate with their chelicerae, producing

1175-455: The Solifugae function partly as sense organs similar to insects' antennae , and partly in locomotion, feeding, and fighting. In normal locomotion, they do not quite touch the ground, but are held out to detect obstacles and prey; in that attitude, they look particularly like an extra pair of legs or perhaps arms. Reflecting the great dependence of the Solifugae on their tactile senses, their anterior true legs commonly are smaller and thinner than

1222-754: The abandoning of a desert region near the Astaboras river (said to be in India, but thought to be a river in Ethiopia). Anton August Heinrich Lichtenstein theorized in 1797 that the "mice" that plagued the Philistines in the Old Testament were Solifugae. During World War I , troops stationed in Abū Qīr , Egypt, would stage fights between captive "jerrymanders", as they referred to them, and placed bets on

1269-400: The body length, quoting leg lengths separately, if at all. The body length is up to 7 cm (3 in). Most species are closer to 5 cm (2 in) long, and some small species are under 1 cm (0.4 in) in head-plus-body length when mature. Like that of spiders, the body plan of the Solifugae has two main tagmata : the prosoma , or cephalothorax , is the anterior tagma, and

1316-507: The desert, solifuges live in a variety of micro-habitats . These include sand dunes , sand flats , floodplains , rocky hillsides, desert shrublands , gravel plains, and mountain valleys. In addition to the desert, certain solifuges live in more arid grasslands and forests. Depending on the species in question, solifuges may be more sedentary or on the move. Sedentary species are often fossorial , living in relatively permanent burrows underground. Transitory species spend most of their time up

1363-490: The fangs of spiders, stings of wasps, or venomous setae of caterpillars (e.g., Lonomia or Acharia species). One 1978 study is frequently quoted, in which the authors report detection of an exception in India , in that Rhagodes nigrocinctus had venom glands, and that injection of the secretion into mice was frequently fatal. However, no supporting studies have confirmed either statement, such as by independent detection of

1410-411: The fifth abdominal segment. Air sacs are attached to the branching tracheae, with tracheoles penetrating the epithelia of internal organs. Hemocyanin , a respiratory pigment common in the hemolymph of many arachnids and other arthropods, is absent. As embryos they also have opisthosomal protuberances resembling the pulmonary sacs found in some palpigrades . Among the most distinctive features of

1457-419: The glands as claimed, or the relevance of the observations, if correct. Even the authors of the original account admitted to having found no means of delivery of the putative venom by the animal, and the only means of administering the material to the mice was by parenteral injection. Given that many non-venoms such as saliva, blood and glandular secretions can be lethal if injected, and that no venomous function

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1504-404: The ground. The only exception is the majority of termite -loving species, as they prefer to be more sedentary. In addition to using their pedipalps, solifuges have a variety of methods to locate prey. These include seeing movements with their eyes , feeling with their long hairlike setae , smelling with their malleoli , and sensing vibrations . How much the animal relies on each sense depends on

1551-452: The males bear a pair of flagella, one on each chelicera. In the accompanying photograph of a male solifuge, one flagellum is just visible near the tip of each chelicera. The flagella, which bend back over the chelicerae, are sometimes called horns and are believed to have some sexual connection, but their function has not yet been clearly explained. Solifuges have a pair of large central eyes known as median ocelli These eyes are oriented at

1598-708: The orders in the zoology part of the Systema Naturae refer to natural groups. Some of his ordinal names are still in use, e.g. Lepidoptera (moths and butterflies) and Diptera (flies, mosquitoes, midges, and gnats). In virology , the International Committee on Taxonomy of Viruses 's virus classification includes fifteen taxomomic ranks to be applied for viruses , viroids and satellite nucleic acids : realm , subrealm , kingdom , subkingdom, phylum , subphylum , class, subclass, order, suborder, family, subfamily , genus, subgenus , and species. There are currently fourteen viral orders, each ending in

1645-671: The outcome. Similarly, British troops stationed in Libya in World War II staged fights between solifuges and scorpions. The Solifugae are the subject of many legends and exaggerations about their size, speed, behavior, appetite, and lethality. They are not especially large, the biggest having a leg span around 12 cm (4.7 in). They are fast on land compared to other invertebrates, with their top speed estimated to be 16 km/h (10 mph). The Solifugae apparently have neither venom glands nor any venom-delivery apparatus such as

1692-404: The pedicel reflects another difference between the Solifugae and spiders, namely that solifuges lack both spinnerets and silk , and do not spin webs . Spiders need considerable mobility of their abdomens in their spinning activities, and the Solifugae have no such adaptation. The prosoma comprises the head, the mouthparts, and the somites that bear the legs and the pedipalps . It is covered by

1739-570: The posterior three pairs of legs are used for running. On the undersides of the coxae and trochanters of the last pair of legs, the Solifugae have fan-shaped sensory organs called malleoli or racquet (or racket) organs. Sometimes, the blades of the malleoli are directed forward, sometimes not. They have been suspected to be sensory organs for the detection of vibrations in the soil, perhaps to detect threats and potential prey or mates. These structures may be chemoreceptors. Males are usually smaller than females, with relatively longer legs. Unlike females,

1786-564: The precursor of the currently used International Code of Nomenclature for algae, fungi, and plants . In the first international Rules of botanical nomenclature from the International Botanical Congress of 1905, the word family ( familia ) was assigned to the rank indicated by the French famille , while order ( ordo ) was reserved for a higher rank, for what in the 19th century had often been named

1833-502: The rank of family (see ordo naturalis , ' natural order '). In French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille (plural: familles ) was used as a French equivalent for this Latin ordo . This equivalence was explicitly stated in the Alphonse Pyramus de Candolle 's Lois de la nomenclature botanique (1868),

1880-507: The shade/shadow provided by the human. Order (biology) What does and does not belong to each order is determined by a taxonomist , as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order

1927-416: The solifuge for the death of their pet dog . An Arizona resident developed painful lesions due to a claimed solifuge bite but could not produce a specimen for confirmation. Though they are not venomous, the powerful chelicerae of a large specimen may inflict a painful nip, but nothing medically significant. Claims that Solifugae aggressively chase people are also untrue, as they are merely trying to stay in

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1974-411: The species. While all hunt on the ground, some species are great climbers, able to search for prey on trees, shrubs, and on artificial structures. Solifuges hunt their prey using three main hunting strategies: stalking, chasing , and ambushing . Depending on the meal's size, prey is seized with the animal's pedipalps or massive chelicerae . When the pedipalps are used, prey is initially caught with

2021-465: The suffix -virales . Tracheole Tracheole (trā'kē-ōl') is a fine respiratory tube of the trachea of an insect or a spider , part of the respiratory system . Tracheoles are about 1 μm in diameter, and they convey oxygen to cells while providing a means for carbon dioxide to escape. Tracheoles branch from the larger tracheae (which can be several mm in diameter) much like capillaries branch from arteries, or twigs from branches of

2068-734: The surface, occasionally seeking refuge in cracks or under rocks and vegetation. Solifuges are carnivores and typically generalists , feeding on a wide variety of prey in their given environment. For most species, insects make up the bulk of their diet. However, these animals have been known to consume anything they can subdue. This includes other arachnids like spiders , scorpions , and smaller solifuges, other arthropods like millipedes , and small lizards , birds , and mammals . Additionally, solifuges are voracious eaters. It's common for adult females to eat so much that they're temporarily unable to walk. When looking for prey , most solifuges rapidly move about while tapping their pedipalps on

2115-411: The very front of its cephalothorax and are placed close together. These eyes have a pigment-cup structure and are covered by a domed outer lens made from the animal's exoskeleton . Below the dome is the animal's retina , a multi-tiered structure with a layer of cells called the vitreous body at its top. Underneath is the thin preretinal membrane, acting as a barrier between the vitreous body above and

2162-418: Was adopted by Systema Naturae 2000 and others. In botany , the ranks of subclass and suborder are secondary ranks pre-defined as respectively above and below the rank of order. Any number of further ranks can be used as long as they are clearly defined. The superorder rank is commonly used, with the ending -anae that was initiated by Armen Takhtajan 's publications from 1966 onwards. The order as

2209-468: Was even speculated upon in this study, there is still no evidence for even one venomous species of solifuge. Because of their unfamiliar spider-like appearance and rapid movements, Solifugae have startled or even frightened many people. This fear was sufficient to drive a family from their home when one was allegedly discovered in a soldier's house in Colchester, England , and caused the family to blame

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