larva

larva
/lahr"veuh/, n., pl. larvae /-vee/.
1. Entomol. the immature, wingless, feeding stage of an insect that undergoes complete metamorphosis. See illus. under metamorphosis.
2. any animal in an analogous immature form.
3. the young of any invertebrate animal.
4. larvae, Rom. Antiq. malignant ghosts, as lemures.
[1645-55; < NL; special use of L larva a ghost, specter, mask, skeleton; akin to LARES]

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Active, feeding stage in the development of many animals, occurring after birth or hatching and before the adult form is reached.

Larvae are structurally different from adults and often are adapted to a different environment. Some species have free-living larvae but sessile (affixed) adults, the moving larvae thus helping to spread the species; others have aquatic larvae but terrestrial adults. Most larvae are tiny; many are dispersed by entering a host's body, where the adult form of the parasite emerges. Many invertebrates (e.g., cnidarians) have simple larvae. Flukes have several larval stages, and annelids, mollusks, and crustaceans have various larval forms. Insect larvae are called caterpillars, grubs, maggots, or worms; the larval stage of many insects may last much longer than the adult stage (e.g., some cicadas live 17 years as larvae and a week as adults). Echinoderms also have larval forms. The larvae of frogs and toads are called tadpoles. See also metamorphosis, pupa.

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plural  larvae , or  larvas 
 stage in the development of many animals, occurring after birth or hatching and before the adult form is reached. These immature, active forms are structurally different from the adults and are adapted to a different environment.

      In some species the larva is free-living and the adult is an attached or nonmobile form; in others the larva is aquatic and the adult lives on land. In forms with nonmobile adults, the mobile larva increases the geographic distribution of the species. Such larvae have well-developed locomotor structures. A larva sometimes functions as a food gatherer—in many species the larval stage occurs at a time when food is abundant—and has a well-developed alimentary system. It stores food so that the transformation to the adult stage can occur. Some larvae function in both dispersion and nutrition.

      The amount of time in the life cycle spent in the larval stage varies among species. Some have long larval periods, either hatching early, metamorphosing into adults late, or both. Some organisms have a short-lived larval phase or no larvae at all.

 Larvae appear in a variety of forms. Many invertebrates (e.g., cnidarians) have a simple ciliated larva called a planula. Flukes have several larval stages, and annelids, mollusks, and crustaceans have various larval forms. The larval forms of the various insects are called caterpillars, grubs, maggots, and nymphs. Echinoderms (e.g., starfish) also have larval forms. The larva of the frog is called a tadpole.
 

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Universalium. 2010.

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Look at other dictionaries:

  • larvă — LÁRVĂ, larve, s.f. Stadiu în dezvoltarea individuală a unor animale la ieşirea din ou, deosebit prin formă şi mod de viaţă de stadiul adult. – Din fr. larve. Trimis de LauraGellner, 17.05.2004. Sursa: DEX 98  LÁRVĂ s. 1. (zool.) (pop.) plod.… …   Dicționar Român

  • LARVA — Ml GRANS, «блуждающая личинка», обозначение кожной б ни, характеризующейся появлением ползучего красноватого валика, передвигающегося по коже и дающего различные фигуры хода. Синонимами L. т. являются обозначения: creeping disease,… …   Большая медицинская энциклопедия

  • Larva — Album par Eivør Pálsdóttir Pays  Féroé, iles !Îles Féroé Sortie …   Wikipédia en Français

  • larva — [lär′və] n. pl. larvae [lär′vē΄] or larvas [L, ghost, specter, akin to lar, household spirit: see LARES] the early, free living, immature form of any animal that changes structurally when it becomes an adult, usually by a complex metamorphosis… …   English World dictionary

  • Larva — Lar va (l[aum]r v[.a]), n.; pl. L. {Larv[ae]} (l[aum]r v[ae]), E. {Larvas} (l[aum]r v[.a]z). [L. larva ghost, specter, mask.] 1. (Zo[ o]l.) Any young insect from the time that it hatches from the egg until it becomes a pupa, or chrysalis. During… …   The Collaborative International Dictionary of English

  • larva — s.f. [dal lat. larva fantasma, maschera ]. 1. (etnol.) [secondo alcune credenze, anima errabonda, e appena visibile, di un defunto] ▶◀ fantasma, lemure, ombra, spettro, spirito. 2. (fig.) a. [creazione della fantasia: questa che abbiamo è… …   Enciclopedia Italiana

  • larva — 1650s, a ghost, specter, from L. larva (pl. larvae), earlier larua ghost, also mask; applied in biological sense 1768 by Linnaeus because immature forms of insects mask the adult forms. On the double sense of the Latin word, Carlo Ginzburg, among …   Etymology dictionary

  • larva — sustantivo femenino 1. Fase del desarrollo de algunos animales en la que ya han abandonado el huevo y se nutren por sí mismos, pero no han alcanzado todavía la fase adulta: Los insectos, los anfibios y algunos peces pasan por etapas de larva …   Diccionario Salamanca de la Lengua Española

  • larva — (Del lat. larva, fantasma). 1. f. Zool. Animal en estado de desarrollo, cuando ha abandonado las cubiertas del huevo y es capaz de nutrirse por sí mismo, pero aún no ha adquirido la forma y la organización propia de los adultos de su especie. 2.… …   Diccionario de la lengua española

  • larva — larva. См. личинка. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • larva — Forma inmadura de un animal, que sufre una metamorfosis antes de alcanzar el estado adulto. Diccionario Mosby Medicina, Enfermería y Ciencias de la Salud, Ediciones Hancourt, S.A. 1999 …   Diccionario médico

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