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.

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]

larva

/lar·va/ (lahr´vah) pl. lar´vae   [L.] an independent, motile, sometimes feeding, developmental stage in the life history of an animal.
larva cur´rens  a variant of larva migrans caused by Strongyloides stercoralis, in which the progression of the linear lesion is much more rapid.
cutaneous larva migrans , larva mi´grans creeping eruption; a convoluted threadlike pruritic, erythematous, papular or vesicular skin eruption that appears to migrate, caused by burrowing beneath the skin of roundworm larvae, particularly Ancylostoma larvae . Also applied to similar lesions caused by other parasites.
ocular larva migrans  infection of the eye with larvae of 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 of nematode larvae in human tissue other than skin; commonly caused by the larvae of Toxocara canis or T. cati, which do not complete their life cycle in humans.

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.

larva

[lär′və] pl. larvae
Etymology: L, specter
the early immature form of an animal, which undergoes metamorphosis to an adult form. It is one of the growth stages for some insects; the state between the egg and the pupolarval stage is the feeding stage in the growth process. larval, adj.

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]

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.

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.

larva

an independent, immature stage in a life cycle in which the stage is unlike the parent and must undergo changes in form and size to reach the adult stage. There may be one or several, three is common, larval stages in the one life cycle. In fish larvae are also called fry.

larva currens
a variant of larva migrans caused by Strongyloides stercoralis, in which the linear progress of the lesions is much more rapid.
cutaneous larva migrans
creeping eruption; a convoluted, thread-like skin eruption in humans and other species which appears to migrate; caused by the burrowing beneath the skin of roundworm larvae, particularly Ancylostoma, Strongyloides and Gnathostoma spp. A. braziliense, A. caninum, B. phlebotomum can cause the disease.
ocular larva migrans
infection of the eye with the 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 of larvae of animal nematodes in human tissues other than skin, commonly caused by larvae of the roundworms Toxocara canis and T. cati.
References in periodicals archive ?
Moreover, 90-95 percent of any larvicide ingested is excreted into the urine within 48 hours.
The next analysis is Reed and Muench analysis to get the toxicity value of a larvicide to Aedes aegypti larvae.
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.
Pupae (or tumblers) rest on the surface of standing water, where they mature into adults unless killed with a larvicide during their larvae stage.
Eugenol, did not show larvicide effects at the maximum concentration tested (12.
Testing for mosquito adulticides or larvicides is typically done by universities and mosquito control or abatement districts, although it may be done by companies or state or federal research organizations, such as the Department of Defense or the U.
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.
Likely breeding places of mosquitoes would be removed and larvicides would be carried out in a safe manner.
The research team led by Ms Khadija Kannady from the Dar es Salaam City Council, Tanzania, suggests that using larvicides to kill mosquito larvae, along with existing malaria interventions, have been found to have a dramatic effect in reducing malaria risk.
Hazelrigg said he'll have a better idea if the spraying will be necessary once he gets the results back soon on how successful efforts by his staff have been to spray larvicides - pesticides intended to kill mosquito larvae - in sewers, storm drains and flood-control channels.