arthropod summary

Know about the structure and classification of arthropods

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Below is the article summary. For the full article, see arthropod.

arthropods
Representative arthropods. Uniramia, the largest of the arthropod subphyla, contains mostly terrestrial insects and myriapods (including centipedes and millipedes). The insects, the largest arthropod class, differ from other arthropods in that they are usually winged and have only three pairs of legs. Members of the Crustacea subphylum are mostly marine-dwelling and include the shrimps, lobsters, crabs, and barnacles. The microscopic water fleas are chiefly found in fresh water and, along with other minute members of this subphylum, are part of the zooplankton. Most members of the Chelicerata subphylum are arachnids, including the spiders, scorpions, ticks, and mites. The trilobites (members of the Trilobita subphylum) are extinct marine arthropods that flourished during the Cambrian Period. Fossilized remains show a body having three longitudinal lobes divided into three regions—head, thorax, and tail.

arthropod, Any member of the largest phylum, Arthropoda, in the animal kingdom. Arthropoda consists of more than one million known invertebrate species in four subphyla: Uniramia (five classes, including insects), Chelicerata (three classes, including arachnids and horseshoe crabs), Crustacea (crustaceans), and Trilobita (trilobites). All arthropods are bilaterally symmetrical and possess a segmented body covered by an exoskeleton containing chitin, which serves as both armour and a surface for muscle attachment. Each body segment may bear a pair of jointed appendages. The phylum includes carnivores, herbivores, omnivores, detritus feeders, filter feeders, and parasites (see parasitism) in nearly all environments, both aquatic and terrestrial.

horseshoe crab Summary

Horseshoe crab, (order Xiphosura), common name of four species of marine arthropods (class Merostomata, subphylum Chelicerata) found on the east coasts of Asia and of North America. Despite their name, these animals are not crabs at all but are related to scorpions, spiders, and extinct trilobites.

daddy longlegs Summary

Daddy longlegs, (order Opiliones), any of more than 6,000 species of arachnids (class Arachnida) that are known for their extremely long and thin legs and for their compact bodies. Daddy longlegs are closely related to scorpions (order Scorpiones) but, because of their appearance, are often

acarid Summary

Acarid, (subclass Acari or Acarida or Acarina), any member of the subgroup of the arthropod class Arachnida that includes the mites and ticks. Some mites are as small as 0.1 mm (0.0039 inch) in length, while the largest ticks are slightly more than 30 mm (1.18 inches) long. Nymphs and adults

scorpion Summary

Scorpion, (order Scorpiones or Scorpionida), any of approximately 1,500 elongated arachnid species characterized by a segmented curved tail tipped with a venomous stinger at the rear of the body and a pair of grasping pincers at the front. Although scorpions are most common and diverse in deserts,