chigger

chigger
/chig"euhr/, n.
1. Also called harvest mite, redbug. the six-legged larva of a mite of the family Trombiculidae, parasitic on humans and other vertebrates, sucking blood and causing severe itching and acting as a vector of scrub typhus and other infectious diseases.
2. chigoe.
Also, jigger.
[1735-45, Amer.; var. of CHIGOE]

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Larva of some 10,000 mite species, ranging in length from 0.

004 to 0.6 in. (0.1–16 mm). Some are terrestrial; others live in freshwater or salt water. They may be predators, scavengers, or plant feeders, and some are pests of humans, either as parasites or as carriers of disease. In North America, the common chigger that attacks humans is found from the Atlantic coast to the Midwest and Mexico. The larva penetrates clothing and, once attached to the skin, injects a fluid that digests tissue and causes severe itching. After feeding, the larva drops to the ground and begins to mature.

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also called  scrub mite,  harvest mite,  bête rouge , or  chigger mite 

      the larva of any of approximately 10,000 species of mites in the invertebrate subclass Acari (the mites and ticks). The name is also erroneously applied to an insect better known as the chigoe, jigger, or jigger flea.

      Chiggers range in length from 0.1 to 16 mm (0.004 to 0.6 inch). The external skeleton is thin and discontinuous. Certain species have eyes, others have none. Spiracles, or breathing pores, when present, are at the base of the first pair of appendages or elsewhere on the front part of the body.

      Some species are terrestrial in habit, while others live in fresh or marine water. Chiggers may be predators, scavengers, parasites, or plant feeders. Various chiggers are pests of man, either as parasites or as carriers of disease. Attacks of chiggers often result in a dermatitis accompanied by intense itching.

      In North America the common chigger that attacks humans is Eutrombicula alfreddugèsi (also called Trombicula irritans). This species occurs from the Atlantic coast to the Midwest and southward to Mexico. The tiny larvae easily penetrate clothing. Once on the skin surface, they attach themselves and inject a fluid that digests tissue and causes severe itching. The surrounding tissue hardens, forming a tube.

      After feeding, the larva drops to the ground and sheds its external skeleton to become a nymph and finally an adult. Nymphs and adults are not parasitic on vertebrates but feed on plant materials and perhaps other arthropods. Eggs are laid singly on the ground or on leaves or stems of low-growing plants.

      Other species of chiggers that were formerly considered to be members of Trombicula but usually are now classified as separate genera include Eutrombicula splendens and E. batatus of North America. In Europe Neotrombicula autumnalis attacks not only humans but also cattle, dogs, horses, and cats. In the East Asia certain species of Leptotrombidium carry the disease known as scrub typhus.

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Universalium. 2010.

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Look at other dictionaries:

  • chigger — n. 1. a small tropical flea ({Tunga penetrans}, formerly {Pulex penetrans}); same as {chigoe}. [Also spelled {chigre}.] Syn: chigoe, chigoe flea, {Tunga penetrans}. [WordNet 1.5] 2. a larval mite of the family {Trombiculidae} that sucks the blood …   The Collaborative International Dictionary of English

  • Chigger — may refer to:* Harvest mite, mites in the family Trombiculidae that live in North American forests and grasslands * Chigoe flea ( Tunga penetrans ), a parasitic arthropod found in tropical climates, especially South America and the West Indies …   Wikipedia

  • chigger — 1756, from W.Indies chigoe (1660s), possibly from Carib, or of African origin (e.g. Wolof and Yoruba jiga insect ) …   Etymology dictionary

  • chigger — ☆ chigger [chig′ər] n. [of Afr orig., as in Wolof jiga, insect ] the tiny, red larva of a family (Trombiculidae) of mites, whose bite causes severe itching …   English World dictionary

  • chigger — The six legged larva of Trombicula species and other members of the family Trombiculidae; a bloodsucking stage of mites that includes the vectors of scrub typhus. * * * chig·ger chig ər, jig n 1) CHIGOE (1) …   Medical dictionary

  • chigger — UK [ˈtʃɪɡə(r)] / US [ˈtʃɪɡər] noun [countable] Word forms chigger : singular chigger plural chiggers a small insect larva, common in warm parts of the US, whose bite causes painful lumps on your skin …   English dictionary

  • chigger — Jigger Jig ger (j[i^]g g[ e]r), n. [A corrupt. of chigre.] 1. (Zo[ o]l.) A species of flea ({Tunga penetrans}, or {Sarcopsylla penetrans}, or {Pulex penetrans}), which burrows beneath the skin; called also {jigger flea}. See {Chigoe}. [1913… …   The Collaborative International Dictionary of English

  • chigger — Chigoe Chig oe, Chigre Chig re, n. [Cf. F. chigue, perh. fr. Catalan chic small, Sp. chico; or of Peruvian origin.] (Zo[ o]l.) A species of flea ({Tunga penetrans}, formerly {Pulex penetrans}), common in the West Indies and South America, which… …   The Collaborative International Dictionary of English

  • Chigger bite — Chigger bites showing characteristic raised and fluid filled center. Chigger bites are a cutaneous condition caused by trombiculid mites.[1]:453 See also List of cutaneous conditi …   Wikipedia

  • Chigger (disambiguation) — A chigger or harvest mite is a mite in the family Trombiculidae that lives in North American forests and grasslands. Chigger may also refer to: Chigoe flea, a parasitic arthropod found in tropical climates, especially South America and the West… …   Wikipedia

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