Scorpions are the most primitive members of all Arachnida. They have changed little since their first appearance in the Silurian period (395,000,000 years ago). Initially aquatic, they became completely terrestrial at the end of the Devonian period and the beginning of the Carboniferous period (345,000,000 years ago). Today they are exclusively land animals. They live for an average of two to six years. Their life span in nature is primarily determined by predation. Scorpions have an articulated body. In all, there are 18 body segments (somites), the first 6 of which have fused. The head and the thorax are fused to a cephalothorax or prosoma (lit. “fore-body”). Each of these fused segments has a single pair of appendages. At the very front there are small tweezer-like chelicerae, the second segment has a pair of pincers (pedipalps) and the others have altogether 4 pairs of legs. The abdomen is divided into a thick pre-abdomen (mesosoma: lit. “middle-body”) with seven segments and a thin articulated post-abdomen or tail (metasoma: lit. “rear-body”). This tail has 5 segments and ends in a knob-like appendix (telson) with a sharp curved sting (aculeus), where the two venom glands have their outlet. The sting is used to kill prey, for defence against aggressors and in some species it also has a role in the courtship display. Ventrally on the first segment of the abdomen there is a small sternal plate. Caudal from the sternal plate is the genital opening which is covered by a small cap (operculum). Behind this, on the third abdominal segment, is a small basal plate on which there are two protuberances which form a typical V-shaped comb (the so-called “pecten”). This is a sensory organ only found in scorpions. Scorpions have a primitive nervous system. There is one pair of median eyes and two to five pairs of lateral eyes. These eyes are simple (ocelli). There are no compound faceted eyes like the large eyes of many insects. There is an open circulation. The blood flows via tissue sinuses. The elongated heart has seven ostia and pumps blood containing haemocyanin (which is a haemoglobin-like oxygen-carrying pigment that contains copper, not iron). The creatures breathe via 4 book lungs which are connected to the outside world via spiracles (respiratory openings) ventrally on the 3rd to 6th abdominal segments. Undigested remains are discharged via the anus. They also have a type of kidney (Malpighian tubules) via which excess nitrogen is discharged in the form of guanine. There are excretory coxal glands at the base of the first pair of legs.

Some scorpion species are long (Hadogenes troglodytes XE “Hadogenes troglodytes: scorpions, taxonomy”  up to 21 cm), others are heavy (Pandinus imperator XE “Pandinus imperator: scorpions, taxonomy, also called the Emperor scorpion; Heterometrus sp.), while others are small (Microtityus waeringi XE “Microtityus waeringi: scorpions, taxonomy” , adult 12 mm). All scorpions are exclusively carnivorous. While they wait for their prey, the tips of the movable fingers of the pedipalps as well as the tips of the comb (chemo- and mechanoreceptors) rest on the ground. A scorpion first grasps its prey (generally insects) with the pedipalps. If the prey is not immediately overpowered, they sting it by bending the tail forwards over the body. The venom is actively injected. The scorpion releases gastrointestinal juices over the prey in order to liquify it and later suck it up. They consume only the body fluids and liquidified tissues of their prey. A meal can last several hours. Some species are cannibalistic.

Because many scorpions live in dry environments, they have become adapted to minimise loss of water. This is made possible in part by a watertight cuticle based on chitin. This has unusual optical characteristics. Scorpions fluoresce with a greenish colour under long-wave UV light. This makes them easy to spot at night with the aid of a UV lamp. The reason for this fluorescence is unclear. Recently moulted scorpions do not fluoresce. The fluorescence is caused by a substance in a thin layer of the cuticle, the so-called hyaline layer. The fluorescent substance might be beta-carboline (tryptophan metabolite), a by-product of the tanning process as the new cuticle hardens. If this layer is preserved in fossils, it also fluoresces. When the animals are preserved in alcohol, after some time the alcohol can also fluoresce.


Scorpion, spiders, ticks and mites are all arthropods. They belong to the Chelicerata, which refers to the structure of the front appendages. Various authors have proposed different classification schemes. These are based inter alia on the form of the sternum, the presence of protuberances on the legs, the morphology of the telson and the number of lateral eyes. The number of trichobothria (small hair-like sensory organs) on the femur of the pedipalps is also used. Thus the Buthidae have a triangular central sternal plate. The other families have a pentagonal sternum. In general it can be said that scorpions with massive claws (Scorpionidae, Chactidae, Diplocentridae, Bothriuridae) are relatively harmless, while the more dangerous species (Buthidae, Vaejovidae) have finer claws. An often heard explanation is that species with massive claws have no difficulty killing their prey, and so do not need powerful venom. Species with thin delicate pedipalps would need extra assistance from powerful venom. It sounds logical, but it is not known if this correct. The colour of the animal is not significant with regard to toxicity. The identification of a scorpion at the species level is a job for specialists. The use of taxonomic keys presumes a good knowledge of the nomenclature, the jargon, the morphology and anatomy of the animals. Drawings are generally diagrams which require some interpretation, for which prior knowledge is necessary. Several species are indistinguishable from one another on morphological grounds. These cryptic species can only be distinguished with chemical or genetic methods.

Taxonomy, families

  • Bothriuridae
  • *Buthidae
  • Caraboctonidae
  • Chactidae
  • Chaerilidae
  • Euscorpiidae
  • *Hemiscorpiidae
  • Iuridae
  • Microcharmidae
  • Pseudo- chactidae
  • *Scorpionidae
  • Superstitioniidae
  • Vaejovidae
  • Akravidae


  • Androctonus. Thick-tailed scorpions: A. australis XE “Androctonus australis: scorpions, taxonomy”  is the most important species in the Old World.
  • Buthus: in the case of Buthus occitanus XE “Buthus occitanus: scorpions, taxonomy” , the major species within this genus, the venom varies sharply in toxicity depending on the geographical region. Buthus tamulus XE “Buthus tamulus: scorpions, taxonomy”  was renamed Buthotus tamulus XE “Buthotus tamulus: scorpions, taxonomy.
  • Mesobuthus (earlier placed within the genus Buthotus): Mesobuthus tamulus XE “Mesobuthus tamulus: scorpions, taxonomy”  or “Red Indian Scorpion” primarily causes cardiovascular problems (hypertension, arrhythmia, pulmonary oedema).
  • Hottentotta and H. minox XE “Hottentotta minox: scorpions, taxonomy”  are often found under the bark of Acacia trees. The sting is painful.
  • Leiurus: Leiurus quinquestriatus XE “Leiurus quinquestriatus: scorpions, taxonomy”  is one of the most frequently encountered scorpions in the Sahel. Although the animal produces relatively little venom, the venom is quite powerful.
  • Compsobuthus and Odonthobuthus: C. acuticarinatus XE “Compsobuthus acuticarinatus: scorpions, taxonomy”  from Egypt and O. doriae XE “Odonthobuthus doriae: scorpions, taxonomy” from Iran are moderately venomous.
  • Parabuthus: Most species are found in South Africa and Namibia. The animals measure 5-14 cm and are brown-yellow to black. The genus is distinguished from others through stridulatory granules on the dorsal side of the first two tail segments. They can make a noise by rubbing their sting over these small knobs. They are very venomous. Local pain and systemic effects and even death can be the result. P. liosoma XE “Parabuthus liosoma: scorpions, taxonomy, P. granulatus XE “Parabuthus granulatus: scorpions, taxonomy, P. transvaalicus XE “Parabuthus transvaalicus: scorpions, taxonomy, P. pallidus XE “Parabuthus pallidus: scorpions, taxonomy”  and P. fulvipes XE “Parabuthus fulvipes: scorpions, taxonomy” are the most notorious species. Parabuthus species are unique in that they can also spray venom in a fine jet. This probably involves a reflex which is triggered when the animal feels threatened. The animal does not aim the jet in a specific direction, but can spray up to 1 metre away and 50 cm high.
  • Centruroides: This genus includes the most important scorpions in the New World. Centruroides suffusus XE “Centruroides suffusus: scorpions, taxonomy”  and C. sculpturatus XE “Centruroides sculpturatus: scorpions, taxonomy”  (= C. exilicauda XE “Centruroides exilicauda: scorpions, taxonomy” ) are notorious. C. suffusus XE “Centruroides suffusus: scorpions, taxonomy”  measures up to 9 cm, is yellow to brown in colour and has two longitudinal stripes on the tergites of the pre-abdomen.
  • Tityus: This genus includes more than 100 species, including T. serrulatus XE “Tityus serrulatus: scorpions, taxonomy” (Brazil). This creature is parthenogenetic. It is fairly common in urban environments and – like T. bahiensis XE “Tityus bahiensis: scorpions, taxonomy”  – enters houses. T. trinitatis XE “Tityus trinitatis: scorpions, taxonomy” is highly venomous and is found in sugar cane fields and cocoa plantations. However, this species is not found in houses.
  • Androctonus
  • Buthus
  • Hottentotta
  • Leiurus
  • Parabuthus
  • Mesobuthus
  • Tityus
  • Centruroides
  • from Morocco and Senegal eastwards to India
  • Mediterranean, Middle East and East Africa
  • Northern Africa and the Middle East
  • East Africa and the Middle East
  • from Sudan to South Africa
  • India, Southern and Central Asia
  • South America
  • USA, Mexico, Central America

Scorpion is a common name for any carnivorous animal The form of scorpions within the arthropod is a slim body with six pairs of attachments comprising four pairs of four legs for walking and one large pair of large bite-sized hooks, tail piece to rear Bent over and a swollen cavity containing the sting specified in the curve. The outer protective cover of the scorpion is tough and durable, protects the good hunter. These creatures, despite having a few eyes, are virtually without vision. The body length of adult scorpions varies from 1-2 cm depending on their type. These are about 3 species of scorpions. Species also vary from yellow, green, olive, brown to black.

Scorpions often trap insects and are important in this respect. They often hunt for black beetles and, if they can, frogs. After the hunt, they bite the prey first, then slice it in their jaws or jaws, and then liquidize it by enzymatic secretion. They have filters in the mouth area that act as filters and prevent small particles from entering the esophagus because the food should only enter the fluid. Therefore, the solid material is discarded as pellets. This is why eating the scorpions lasts and sometimes takes up to 24 hours. Scorpions also need water, and scorpions in humid areas usually drink water separately, and scorpions in dry areas provide the water needed to prey. After eating, scorpions spend hours cleaning themselves and cleaning their feet and guttering with fluids from their mouths. Scorpions are highly resistant to hunger and thirst so they can survive for months without water and food.

Scorpions are spiders and arthropods whose traces have been found in the fossils of the Silurian period, about 420 million years ago. This indicates the presence of scorpions before they were found. Is becoming dinosaurs. In general, the scorpion order consists of 28 families that are extinct in about half of these families. Current living species include 14 families, which include more than 1600 species and are grouped into more than 200 genera. . Scorpions have been known to humans for centuries because of their special appearance. They are widespread throughout the world and have been found in deserts, forests, meadows, seashores, and around rivers and mountains. Scorpions have a relatively wide and elongated body, varying in size from 3 to 10 cm, but the largest of these is the African type, which reaches 21 cm in length.


Like other spider-like animals, the scorpion’s body consists of a section in the front called the head and a back section called the abdomen. The back is divided into the middle and posterior regions, which include the abdomen and tail. The head looks like a piece, but the middle and posterior portions are banded. On the sides are the tongs and legs and in front of it are the jaws. All of these members are banded. The abdominal surface is almost completely covered by the last band of tongs, legs, attachments, and a single plaque called the sternum. The abdominal surface is called sternite. On the dorsal surface there are seven bands and on the abdominal surface only five bands can be counted. At the mid-ventral surface, organs such as the respiratory tract, shoulders, and genital cap are seen. The posterior or caudal part is narrower than the trunk and consists of five bands. The poisonous bite and bite are located at the posterior end.

Headache and its Appendices

This part is also called the cephalotrax, which is the anterior part of the scorpion’s body and is covered by a chitinous and trapezoidal one-piece cover called a spacer. It may be a simple or decorative spacer. On either side of the long axis of the head, in the medial-anterior position, there are two protrusions that carry two large middle eyes. 2 to 3 lateral eyes at the lateral-anterior angle are seen in the form of small, clear protrusions. The goose scorpions are without eyes. The anterior edge of the head, called the forehead, may be straight, convex or concave. The posterior edge of the spacer is associated with the first abdominal cavity. Some headaches on the abdominal surface are not completely clear and are covered with full-length coccyx. The head region is six pairs in the abdominal region.

Abdominal area attachments

۱-Oral jaw:

 The clavicles are in the form of two small, fully movable clamps in the anterior region of the abdomen. The chisels are used to cut prey. The cleavage consists of three straps. The two anterior strands form a small clasp that has one fixed finger and one movable finger. The large, fixed finger and abdominal surface covered with dense hair form the upper wall of the oral cavity. The curved finger resembles a fixed tooth, and may be attached to a single branch or two branch scorpions. The abdominal surface of the movable finger is also covered with hair. The third section or basal section is subdivided. The inner surface of this section is divided into two sections by a soft chitinous membrane.

۲-Tweezers or Patties:

The tongs have more growth than any other attachment. The tongs are made of six strands. These strands, like the strings, have different names. Scorpions have given different names to the tongs and strings. The first herringbone strap that connects directly to the body is called the coxa or hanisch, which forms the lateral walls of the oral cavity. Their inner surface, which is related to the oral cavity, is covered with me. In some scorpions, the heterometrous remnant, on the surface of these bands, which is associated with the same strap on the first legs, can be seen with several hard and curved khargs. The second to fourth clusters are: trochanter perforum and femur. The last two bands, the fifth and sixth bands, have become relatively large clasps. One of these bands, which is removable, is called the removable finger or post-tarsus, and the other is called the fixed or tibial finger.

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