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A larva (plural larvae ) is a distinct juvenile form many
animal Animals (also called Metazoa) are multicellular A multicellular organism is an organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All organisms are composed of cells ...

animal
s undergo before
metamorphosis Metamorphosis is a biological process Biological processes are those processes that are vital for an organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All organisms are ...
into
adult Biology, Biologically, an adult is an organism that has reached sexual maturity. In human context, the term ''adult'' has meanings associated with social and Law, legal concepts. In contrast to a "Minor (law), minor", a legal adult is a person ...

adult
s. Animals with indirect
development Development or developing may refer to: Arts *Development hell, when a project is stuck in development *Filmmaking#Development, Filmmaking, development phase, including finance and budgeting *Development (music), the process thematic material i ...
such as
insect Insects (from Latin Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication Communication (from Latin ''communicare'', meaning "to share" or "to be in ...

insect
s,
amphibian Amphibians are ectothermic, tetrapod vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial animal, ter ...
s, or
cnidaria Pacific sea nettles, ''Chrysaora fuscescens'' Cnidaria () is a phylum In biology, a phylum (; plural The plural (sometimes list of glossing abbreviations, abbreviated ), in many languages, is one of the values of the grammatical number, ...

cnidaria
ns typically have a larval phase of their
life cycle Life cycle, life-cycle, or lifecycle may refer to: Science and academia *Biological life cycle, the sequence of life stages that an organism undergoes from birth to reproduction ending with the production of the offspring *Life-cycle hypothesis, ...
. The larva's appearance is generally very different from the adult form (''e.g.''
caterpillar Caterpillars ( ) are the larva, larval stage of members of the order Lepidoptera (the insect order comprising butterfly, butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawfly ...

caterpillar
s and
butterflies Butterflies are insect Insects (from Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken in the area around Rome, known as Latiu ...

butterflies
) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as
tadpoles A tadpole is the Larva, larval stage in the life cycle of an amphibian. Most tadpoles are fully Aquatic animal, aquatic, though some species of amphibians have tadpoles that are terrestrial animal, terrestrial. Tadpoles have some features that m ...
live almost exclusively in aquatic environments, but can live outside water as adult
frogs A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (literally ''without tail'' in Ancient Greek). The Triadobatrachus, oldest fossil "proto- ...
. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like
polychaete The Polychaeta , also known as the bristle worms or polychaetes, are a paraphyletic class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ...

polychaete
s and
barnacles A barnacle is a type of arthropod An arthropod (, (gen. ποδός)) is an invertebrate animal having an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Euarthropoda,Reference sh ...

barnacles
, adults are immobile but their larvae are mobile, and use their mobile larval form to distribute themselves. Some larvae are dependent on adults to feed them. In many eusocial
Hymenoptera Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Para ...

Hymenoptera
species, the larvae are fed by female workers. In ''
Ropalidia marginata ''Ropalidia marginata'' is an Old World The Old World consists of Africa Africa is the world's second-largest and second-most populous continent A continent is one of several large landmasses. Generally identified by con ...

Ropalidia marginata
'' (a paper wasp) the males are also capable of feeding larvae but they are much less efficient, spending more time and getting less food to the larvae. The larvae of some organisms (for example, some
newt A newt is a salamander Salamanders are a group of amphibians typically characterized by a lizard Lizards are a widespread group of Squamata, squamate reptiles, with over 6,000 species, ranging across all continents except Antarctica, ...

newt
s) can become
pubescent Puberty is the process of physical changes through which a child Biologically, a child (plural children) is a human Humans (''Homo sapiens'') are the most populous and widespread species of primates, characterized by bipedality, opp ...

pubescent
and do not develop further into the adult form. This is a type of
neoteny Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-d ...

neoteny
. It is a misunderstanding that the larval form always reflects the group's evolutionary history. This could be the case, but often the larval stage has evolved secondarily, as in insects. In these cases the larval form may differ more than the adult form from the group's common origin.


Selected types of larvae


Insect larvae

Within
Insects Insects (from Latin ') are pancrustacean Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, Thorax (ins ...

Insects
, only
Endopterygote Endopterygota (from Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following perio ...
s show complete metamorphosis, including a distinct larval stage. Several classifications have been suggested by many
entomologists upright=1.2, A Phyllium sp., mimicking a leaf Entomology () is the scientific Science (from the Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was or ...
, and following classification is based on
Antonio BerleseImage:Berlese Antonio 1863-1927.png, 180px, Antonio Berlese Antonio Berlese (26 June 1863 in Padua – 24 October 1927 in Florence) was an Italy, Italian entomologist. Berlese worked on economic entomology, pest insects notably of fruit trees. He p ...
classification in 1913. There are four main types of endopterygote larvae types: #Apodous larvae – no legs at all and are poorly sclerotized. Based on
sclerotizationSclerotin is a component of the cuticles of various Arthropoda, most familiarly insects. It is formed by Cross-link, cross-linking members of particular classes of protein molecules, a biochemical process called sclerotization. Technically it amounts ...
, three apodous forms are recognized. #*Eucephalous – with well sclerotized head capsule. Found in
Nematocera The Nematocera (the name means "thread-horns") are a suborder of elongated flies with thin, segmented antennae and mostly aquatic larva A larva (plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adult ...
,
Buprestidae Buprestidae is a family In human society, family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of families is to maintain the w ...
and
Cerambycidae
Cerambycidae
families. #*Hemicephalus – with a reduced head capsule, retractable in to the thorax. Found in
Tipulidae Crane fly is a common name referring to any member of the insect family (biology), family Tipulidae, of the order fly, Diptera, true fly, flies in the superfamily Tipuloidea. Cylindrotominae, Limoniinae, and Pediciinae have been ranked as subfam ...

Tipulidae
and
Brachycera The Brachycera are a suborder In biological classification, the order ( la, wikt:ordo#Latin, ordo) is # a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. The well-known ranks in descending order ...
families. #*Acephalus – without head capsule. Found in
Cyclorrhapha Cyclorrhapha is an unranked taxon within the infraorder In biological classification In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemi ...
#Protopod larvae – larva have many different forms and often unlike a normal insect form. They hatch from eggs which contains very little
yolk Among animals which produce eggs, the yolk (; also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example beca ...

yolk
. E.g. first
instar An instar (, from the Latin ''īnstar'', "form", "likeness") is a developmental stage of arthropods An arthropod (, (gen. ποδός)) is an invertebrate Invertebrates are animals that neither possess nor develop a vertebral column (commonly ...
larvae of parasitic hymenoptera. #Polypod larvae – also known as eruciform larvae, these larva have abdominal prolegs, in addition to usual thoracic legs. They poorly sclerotized and relatively inactive. They live in close contact with the food. Best example is
caterpillar Caterpillars ( ) are the larva, larval stage of members of the order Lepidoptera (the insect order comprising butterfly, butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawfly ...

caterpillar
s of lepidopterans. #Oligopod larvae – have well developed head capsule and mouthparts are similar to the adult, but without compound eyes. They have six legs. No abdominal prolegs. Two types can be seen: #*Campodeiform – well sclerotized, dorso-ventrally flattened body. Usually long legged predators with prognathous mouthparts. (lacewing, trichopterans, mayflies and some coleopterans). #*Scarabeiform – poorly sclerotized, flat thorax and abdomen. Usually short legged and inactive burrowing forms. (
Scarabaeoidea Scarabaeoidea is a superfamily of beetle Beetles are a group of insects that form the Taxonomic rank, order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, Elytron, elytra, distinguis ...
and other coleopterans).


See also

*
Crustacean larvae Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult In biology Biology is the natural science that studies life and l ...

Crustacean larvae
*
Ichthyoplankton Ichthyoplankton (from Greek: ἰχθύς, , "fish"; and πλαγκτός, , "drifter") are the eggs and larvae of fish. They are mostly found in the sunlit zone of the water column, less than 200 metres deep, which is sometimes called the e ...
*
Spawn (biology) Spawn is the eggs Egg An egg is the organic vessel containing the in which an develops until it can survive on its own, at which point the animal hatches. An egg results from of an . Most s, (excluding s), and lay eggs, althou ...
* Non-larval animal
juvenile Juvenile may refer to: *Juvenile status, or minor (law), prior to adulthood *Juvenile (organism) *Juvenile (rapper) (born 1975), American rapper *Juvenile (2000 film), ''Juvenile'' (2000 film), Japanese film *Juvenile (2017 film), ''Juvenile'' (20 ...
(immature) stages and other
life cycle Life cycle, life-cycle, or lifecycle may refer to: Science and academia *Biological life cycle, the sequence of life stages that an organism undergoes from birth to reproduction ending with the production of the offspring *Life-cycle hypothesis, ...
stages: ** In
Porifera Sponges, the members of the phylum In biology, a phylum (; plural The plural (sometimes list of glossing abbreviations, abbreviated ), in many languages, is one of the values of the grammatical number, grammatical category of number. Th ...

Porifera
: olynthus,
gemmule Gemmules are internal buds found in sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal Metazoa (animal) clade A clade (; from grc, , ''klados'', "branch"), also known as a monophyletic group ...
** In
Cnidaria Pacific sea nettles, ''Chrysaora fuscescens'' Cnidaria () is a phylum In biology, a phylum (; plural The plural (sometimes list of glossing abbreviations, abbreviated ), in many languages, is one of the values of the grammatical number, ...

Cnidaria
:
ephyra
ephyra
, scyphistoma, strobila,
gonangium {{Short pages monitor