arachnid (ərăk`nĭd), mainly terrestrial arthropod of the class Arachnida, including the spider spider, organism, mostly terrestrial, of the class Arachnida, order Araneae, with four pairs of legs and a two-part body consisting of a cephalothorax, or prosoma, and an unsegmented abdomen, or opisthosoma.
..... Click the link for more information. , scorpion scorpion, any arachnid of the order Scorpionida with a hollow poisonous stinger at the tip of the tail. Scorpions vary from about 1/2 in. to about 6 in. (1–15 cm) long; most are from 1 to 3 in. (2.5–7.6 cm) long.
..... Click the link for more information. , mite mite, small, often microscopic chelicerate that, along with the tick, makes up the order Acarina; it is also related to spiders. The unsegmented mite body is typically oval and compact, although a few, mostly parasites, are elongated and wormlike.
..... Click the link for more information. and tick, harvestman harvestman, arachnid, often called daddy longlegs because of its eight long, slender legs. The harvestman has a rounded or oval body possessing glands that give off an acrid scent.
..... Click the link for more information. (daddy longlegs), and a few minor groups. The body is divided into a cephalothorax with six pairs of appendages, and an abdomen. The first two pairs of appendages are used to kill and crush prey (most arachnids being carnivorous); the remaining four pairs are walking legs. Arachnids have simple eyes and no antennae but are equipped with sensory bristles. Some respire with air tubes, but most possess primitive respiratory organs called book lungs book lung, terrestrial respiratory organ characteristic of arachnids such as scorpions and primitive spiders. Each book lung consists of hollow flat plates. Air bathes the outer surface of the plates and blood circulates within them, facilitating the exchange of
..... Click the link for more information. . Arachnids are classified in the phylum Chelicerata Chelicerata , phylum of the living horseshoe crabs (class Merostomata), the arachnids (class Arachnida), and the sea spiders (class Pycnogonida). Chelicerates are characterized by the absence of antennae and jaws and the presence of feeding structures (chelicera),
..... Click the link for more information. , class Arachnida.

arachnid

Any member of the class Arachnida, primarily carnivorous arthropods having a well-developed head, a hard external skeleton, and four pairs of walking legs. Spiders and scorpions have a segmented body, but daddy longlegs, ticks, and mites do not. Arachnids range in size from tiny mites (0.003 in. [0.08 mm] long) to the 8-in. (21-cm) black scorpion of Africa. As arachnids grow, they molt several times (see molting). Most are unable to digest food internally; instead, they inject their prey with digestive fluids and suck the liquefied remains. Arachnids are found worldwide in nearly every habitat. Most groups are free-living, but some mites and ticks are parasitic and can carry serious diseases of animals and humans. Venomous spiders and scorpions also may pose a danger to humans. However, most arachnids are harmless and prey on insect pests.

arachnid

any terrestrial chelicerate arthropod of the class Arachnida, characterized by simple eyes and four pairs of legs. The group includes the spiders, scorpions, ticks, mites, and harvestmen

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No references found	Mike Carter discovered the arachnid while carrying out work on a pillar outside a house in Leixlip, Co Kildare. Zoo's red alert; SPIDER MISTAKEN FOR KILLER REDBACK FROM AUSTRALIA ... by The Mirror (London, England) The supermarket staff captured the arachnid in a plastic box before contacting the SSPCA. BANANA DRAMA; Poisonous scorpion found in supermarket fruit box by Daily Record (Glasgow, Scotland) Experts at Wuhan University claim that they are the first research team to have analysed venom in this arachnid, and discovered nine novel poison molecules, never before seen in any scorpion species. Secrets ingredients of scorpion venom unraveled by Asian News International	arabic numerals Arabic philosophy Arabic Script Arabic Studies Arabika arabine arabinose Arabis Arabistan arabite arabitol Arable Land Arablinskii, Gusein Mamed Ogly Arabs Arabs of Middle Asia Aracaju Araceae arachic acid arachidic acid arachidonate arachidonic acid Arachis arachis oil Arachne Arachnia arachnid Arachnida arachniography arachnodactyly arachnoid arachnoid villi arachnoidal granulations Arachnoidea Arachnoiditis arachnology arachnophobia Arachnoses Arachosia Arad Aradan Range Aradidae Aradoidea Aradus Araeoscelidia araeostyle araeosystyle Arafat Arafat, Mt Arafat, Yasir Arafura Sea Aragats	Arachis hypogaea Arachis hypogaea Arachis hypogaea Arachis hypogaea Arachis oil Arachis oil Arachis oil arachn- Arachnaphobia Arachnaphobia Arachnaphobia Arachne Arachne Arachne Arachné Arachné Arachné Arachnea Arachnea Arachnea Arachnea Arachnea arachnephobia arachnephobia arachnephobia Arachnia Arachnia propionica Arachnia propionica Arachnia propionica arachnic injury arachnid Arachnida Arachnida Arachnida Arachnida arachnidan arachnidan arachnidan arachnidan Arachnidial arachnidian arachnidism Arachnidium Arachnids Arachnids Arachnids Arachnids arachniography Arachniphobia Arachniphobia Arachniphobia Arachnitis Arachnitis arachno- arachnodactyly arachnodactyly Arachnodes arachnoid arachnoid arachnoid Arachnoid (brain)

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Mike Carter discovered the arachnid while carrying out work on a pillar outside a house in Leixlip, Co Kildare.

Zoo's red alert; SPIDER MISTAKEN FOR KILLER REDBACK FROM AUSTRALIA ... by The Mirror (London, England)

The supermarket staff captured the arachnid in a plastic box before contacting the SSPCA.

BANANA DRAMA; Poisonous scorpion found in supermarket fruit box by Daily Record (Glasgow, Scotland)

Experts at Wuhan University claim that they are the first research team to have analysed venom in this arachnid, and discovered nine novel poison molecules, never before seen in any scorpion species.

Secrets ingredients of scorpion venom unraveled by Asian News International

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arachnid

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