arachnid


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arachnid

(ərăk`nĭd), mainly terrestrial arthropod of the class Arachnida, including the spiderspider,
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.
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, scorpionscorpion,
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.
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, mitemite,
small, often microscopic arachnid that belongs to several orders in the subclass Acari (or Acarina), to which the tick also belongs; mites and ticks are related to the spiders.
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, ticktick,
small, parasitic arachnid of the order Ixodida, closely related to the mites. Ticks, which are larger than the often microscopic mites, are all parasitic in at least one developmental stage; most parasitize mammals and birds although some have reptilian and amphibian hosts.
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, harvestmanharvestman,
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.
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 (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 lungsbook 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 gases.
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. Arachnids are classified in the phylum ArthropodaArthropoda
[Gr.,=jointed feet], largest and most diverse animal phylum. The arthropods include crustaceans, insects, centipedes, millipedes, spiders, scorpions, and the extinct trilobites.
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, subphylum ChelicerataChelicerata
, subphylum of Arthropoda, including the horseshoe crabs (order Xiphosura), the arachnids (class Arachnida), and the sea spiders (class Pycnogonida). The extinct giant water scorpions (order Eurypterida, not true scorpions) also are chelicerates.
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, class Arachnida.

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
References in periodicals archive ?
(3.) Use a skills sheet to ask questions about arachnid adaptations.
This does not leave me particularly reassured, especially when Duncan continues his discussion of Cyprus' bigger arachnids: "We have a very interesting mix of spiders, which includes largish spiders like the aforementioned tarantula Chaetopelmaolivaceum -- Europe's largest spider." This is a spider, he tells me, which can grow up to 12cm in leg span and may have a body length of up to 4cm (spiders are always measured by body length).
The financial terms of the deal were not disclosed.The addition of Arachnid is in line with Publicisa[euro](tm) strategic objectives for both, the digital segment and fast-growing markets, which make up the two pillars of its global growth, it said.
9 October 2012 - French advertising major Publicis Groupe SA (EPA:PUB) said on Tuesday it had taken over Malaysian digital agency Arachnid, in a move that added substantial scale to its digital capabilities in the Asia Pacific region.
What is the smallest member of the arachnid family?
Humans, we learn from Federal Network broadcasts, may have unwittingly provoked the Arachnids when "Mormon extremists" settled inside the Arachnid zone of the galaxy.
Humans, we learn from Federal Network broadcasts, actually might have provoked the Arachnids when "Mormon extremists" settled inside the Arachnid zone of the universe.
Scorpiones.--Whereas the fossil record of most (extant) arachnid orders is skewed towards the Cenozoic by large numbers of amber species, the scorpion fossil record is uniquely more diverse in the Paleozoic (Table 1).
A SPIDER is an arachnid, which has a two-part body, eight legs and two pincers.
To us thick-skinned humans, this attenuated arachnid is entirely harmless.
One boasting an ethnic African-American single female whose husband has passed away...an eight-legged web-spinning arachnid belonging to the insectivorous order.