larva

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larva

 [lahr´vah] (pl. lar´vae) (L.)
1. an independent, immature stage in the life cycle of an animal, in which it is markedly unlike the parent and must undergo changes in form and size to reach the adult stage.
2. something that resembles such an immature animal.
larva cur´rens a rapidly progressive creeping eruption caused by autoinoculation of larvae of Strongyloides stercoralis that migrate to and mature at the anus in intestinal infections with the parasite.
cutaneous larva mi´grans (larva mi´grans) a convoluted threadlike skin eruption that appears to migrate, caused by the burrowing beneath the skin of roundworm larvae, particularly of the species Ancylostoma; similar lesions are caused by the larvae of botflies. Called also creeping eruption.
ocular larva migrans infection of the eye with larvae of the roundworm Toxocara canis or T. cati, which may lodge in the choroid or retina or migrate to the vitreous; on the death of the larvae, a granulomatous inflammation occurs, the lesion varying from a translucent elevation of the retina to massive retinal detachment and pseudoglioma.
visceral larva migrans a condition due to prolonged migration by the skin larvae of animal nematodes in human tissue other than skin; commonly caused by larvae of the roundworms Toxocara canis and T. cati.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

lar·va

, pl.

lar·vae

(lar'vă, lar'vē),
1. The wormlike developmental stage or stages of an insect or helminth that are markedly different from the adult and undergo subsequent metamorphosis; a grub, maggot, or caterpillar.
2. The second stage in the life cycle of a tick; the stage that hatches from the egg and, following engorgement, molts into the nymph.
3. The young of fishes or amphibians that often differ in appearance from the adult.
[L. a mask]
Farlex Partner Medical Dictionary © Farlex 2012

larva

(lär′və)
n. pl. lar·vae (-vē) or lar·vas
1.
a. The newly hatched, wingless, often wormlike form of many insects, developing into a pupa in species that undergo complete metamorphosis.
b. The six-legged immature form of a tick or mite.
2. The newly hatched, earliest form of any of various animals that undergo metamorphosis, differing markedly in appearance from the adult.

lar′val adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

lar·va

, pl. larvae (lahr'vă, -vē)
1. Developmental stage or stages of an insect or helminth.
2. The second stage in the life cycle of a tick; the stage in which it hatches from the egg and, following engorgement, molts into the nymph.
3. The young of fishes or amphibians that often differ in appearance from the adult.
[L. a mask]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

larva

(pl. larvae) the preadult form of many animals that is usually morphologically different from the adult, and which in many cases takes up the larger part of the life history. Usually the larva is not sexually mature, but in cases of PAEDOGENESIS, of which the AXOLOTL is an example, breeding may take place at this stage. Often the larva is a dispersal phase, as in many marine invertebrates where larvae occur in the PLANKTON and usually the larva feeds in a different way from the adult and does not compete with it.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

Larva

The immature, early form of an organism that at birth or hatching is not like its parent and has to undergo metamorphosis before assuming adult features.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Moreover, 90-95 percent of any larvicide ingested is excreted into the urine within 48 hours.
This study was an experimental research with the posttest only control group design, which aimed to find out the effect of salam leaf extract (Syzygium polyanthum W.) as larvicide against Aedes aegypti L.
To determine possible effect of time periods on the efficacy of two larvicides under semi field conditions mean larval mortalities were compared using analysis of variance
The nanoparticles obtained for the larvicides, temephos and pirimiphos-methyl and the IGR, DPE28 were characterized using a scanning electron microscope (SEM-Hitachi S 3400) that scanned the surface of the sample in a raster pattern, utilizing an electron beam.
According to American Vanguard Corporation, Bti Briquets provides a versatile, efficient, cost- effective and environmentally compliant treatment which has contributed to successful larvicide control for more than three decades in US and international public health markets.
In a pilot study three wards of the city, covering 128,000 inhabitants, were treated with microbial larvicide .
Adulticides kill adult mosquitoes and can be used in tandem with larvicides. They are necessary when adult mosquitoes migrate into an area, or when an outbreak of disease poses a health threat to a community.
Results of the study were tabulated, and a Chi-square test was performed to assess the statistical significance of the effect of the larvicide. A cutoff p-value of .05 was established.
Eugenol, did not show larvicide effects at the maximum concentration tested (12.5 [micro]g/ml).
Mosquito control in the United States has evolved from reliance on insecticide application for control of adult mosquitoes (adulticide) to integrated pest management programs that include surveillance, source reduction, larvicide, and biological control, as well as public relations and education.
The recent negative consumer perceptions concerning the use of chemicals as larvicides has shifted the research effort towards the development of alternatives that the public perceives as natural, such as essential oils and plant extracts.