Word Finder - larva

definition

An early stage of growth for some insects and amphibians, in which after hatching from their egg, insects are wingless and resemble a caterpillar or grub, and amphibians lack limbs and resemble fish.

definition

An animal in the aforementioned stage.

definition

A form of a recently born or hatched animal that is quite different from its adult stage.

The irritation set up by the hatching egg and its resulting larva appears to be the stimulus to development, and net a poison or enzyme injected by the insect.

A full-grown larva digs a pit about 2 in.

The beetles are fierce Antenna of Larva of Gyrinus.

The larva pierces the vessels of the plant with sharp processes at the hinder end of its body.

The carabid larva is an active well-armoured grub with the legs and cerci variable in length.

At the end of this stage, the larva will spin a cocoon.

The most striking feature in the development of beetles is the great diversity noticeable in the outward form of the larva in different families.

The female is viviparous, and the young, which, unlike the parent, are provided with a long tail, live free in water; it was formerly believed from the frequency with which the legs and feet were attacked by this parasite that the embryo entered the skin directly from the water, but it has been shown by Fedschenko, and confirmed by Manson, Leiper and others, that the larva bores its way into the body of a Cyclops and there undergoes further development.

In those Euthyneura in which the shell is entirely absent in the adult, it is, except in the three genera Cenia, Runcina and Vaginula, developed in the larva and then falls off.

The chief modifications of this form are seen in the Mitraria larva of Ammochares with only the preoral band, which is much folded and which has provisional and long setae; the a.trochous larva, where the covering of cilia is uniform and not split into bands; and the polytrochous larva where there are several bands surrounding the body.

It is absurd to call the larva of a newt or of a Caecilian a tadpole, nor is the free-swimming embryo of a frog as it leaves the egg a tadpole.

The larva has a breathing-tube, and floats head downwards; when disturbed it wriggles to the bottom (Christy).

He referred also to the nautiloid shell of the larva falling to one side.

From the egg a larva arises.

After eating the contents of the egg, the larva moults and becomes a fleshy grub with short legs and with paired spiracles close to the dorsal region, so that, as it floats in and devours the honey, it obtains a supply of air.

The fate of the larva is unknown.

Monthly preventative heartworm medication kills the larva that entered into the dog's body over the past 30 to 45 days.

Daily medication is only effective in killing any larva that entered the dog's body during the past 24 to 48 hours.

The majority of the flea infestation is made up fleas in various life cycle stages, meaning eggs, larva or the pupa.

From fecund egg to ravenous caterpillar (larva) to metamorphosing pupa to parental adult, the butterfly's life is profoundly meaningful.

Fabre states that the mother-insect carefully arranges the food-supply so that the most nutritious and easily digested portion is nearest the egg, to form the first meal of the young larva.

Such a young insect is a larva - a term used by zoologists for young animals generally that are decidedly unlike their parents.

It is obvious that the hatching of the young as a larva necessitates h After Heymons, Zeit.

These later stages, comprising the greater part of the larval history, are adapted for an inquiline or a parasitic life, where shelter is assured and food abundant, while the short-lived, active condition enables the newly-hatched insect to make its way to the spot favourable for its future development, clinging, for example, in the case of an oil-beetle's larva, to the hairs of a bee as she flies towards her nest.

Fragmentary as the records are, they show that the Exopterygota preceded the Endopterygota in the evolution of the class, and that among the Endopterygota those orders in which the greatest difference exists between imago and larva - the Lepidoptera, Diptera and Hymenoptera - were the latest to take their rise.

Some of those zoologists who look to Peripatus, or a similar worm-like form, as representing the direct ancestors of the Hexapoda have laid stress on a larva like the caterpillar of a moth or saw-fly as representing a primitive stage.

Bionomically, metamorphosis may be defined as the sum of adaptations that have gradually fitted the larva (caterpillar or maggot) for one kind of life, the fly for another.

The oldest larva known, Mormolucoides articulatus, is from the New Red Sandstone of Connecticut; it belongs to the Sialidae, one of the lowest forms of Holometabola.

As the life-conditions and feedinghabits of the larva and imago become constantly more divergent, the appearance of the wing-rudiments would be postponed to the pre-imaginal instar, and that instar would become predominantly passive.

The Neuroptera, with their similar foreand hind-wings and their campodeiform larvae, seem to stand nearest to the presumed isopteroid ancestry, but the imago and larva are often specialized.

The antiquity of the Coleoptera is further shown by the great diversity of larval form and habit that has arisen in the order, and the proof afforded by the hypermetamorphic beetles that the campodeiform preceded the eruciform larva has already been emphasized.

In all the remaining orders of the Endopterygota the larva is eruciform or vermiform.

The eruciform larva of the Orthorrhapha leads on to the headless vermiform maggot of the Cyclorrhapha, and in the latter sub-order we find metamorphosis carried to its extreme point, the muscid flies being the most highly specialized of all the Hexapoda as regards structure, while their maggots are the most degraded of all insect larvae.

The Siphonaptera appear by the form of the larva and the nature of the metamorphosis to be akin to the Orthorrhapha - in which division they have indeed been included by many students.

In some way it is assured among the highest of the Hexapoda - the Lepidoptera, Diptera and Hymenoptera - that the larva finds itself amid a rich food-supply.

And thus perfection of structure and instinct in the imago has been accompanied by degradation in the larva, and by an increase in the extent of transformation and in the degree of reconstruction before and during the pupal stage.

Aristotle and Harvey (De generatione animalium, 1651) had considered the insect larva as a prematurely hatched embryo and the pupa as a second egg.

In origin the vascular system is due to a fusion of spaces which arise in the mesoblast of the larva.

The larva of Cerebratulus is called the pilidium.

In accordance with these more sedentary habits during the first phases of life, the characteristic pilidium larva, which is so eminently adapted for a pelagic existence, appears to have been reduced to a close-fitting exterior layer of cells, which is stripped off after the definite body-wall of the Nemertine has similarly originated out of four ingrowths from the primary epiblast.

To this reduced and sedentary pilidium the name of " larva of Desor " has been given.

A curious feature shared by both larva and adult is the large size of many of the cells, e.g.

A, The larva of Echinorhynchus proteus from the body cavity of Phoxinus laevis, with the proboscis retracted and the whole still enclosed in a capsule.

The Tornaria larva offers a certain similarity to larvae of Echinoderms (sea-urchins, star-fishes, and sea-cucumbers), and when first discovered was so described.

As in the case of the Lamellibranchiata, the shell of the adult is not a direct derivative of the youngest shell of the larva.

By the aid of these cilia the larva swims actively, but owing to its minute size it covers very little distance, and this probably accounts for the fact that where brachiopods occur there are, as a rule, a good many in one spot.

After a certain time the larva fixes itself by its stalk to some stone or rock, and the skirt-like second segment turns forward over the head and forms the mantle.

The cirri or tentacles, of which three or four pairs are present, are capable of being protruded, and the minute larva swims by means of the ciliary action they produce.

Either before or just after turning, the mantle develops a larval shell termed the protegulum, and when this is completed the larva is termed the Phylembryo.

The larva now assumes specific characters and is practically adult.