A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...
s undergoing transformation between immature and mature stages. Insects that go through a pupal stage are
holometabolous
Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the superorder Endopterygota. ...
: they go through four distinct stages in their life cycle, the stages thereof being egg,
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
, pupa, and
imago
In biology, the imago (Latin for "image") is the last stage an insect attains during its metamorphosis, its process of growth and development; it is also called the imaginal stage, the stage in which the insect attains maturity. It follows the f ...
. The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially
juvenile hormone Juvenile hormones (JHs) are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. The first discovery of a JH was by Vincent Wigglesworth. JHs regulate development, reproduction, diapause, and polyphenisms.The chem ...
,
prothoracicotropic hormone Prothoracicotropic hormone (PTTH) was the first insect hormone to be discovered.The chemical symbol for prothoracicotropic hormone is (C64H102N16O19S2). It was originally described simply as "brain hormone" by early workers such as Stefan Kopeć (1 ...
, and
ecdysone
Ecdysone is a prohormone of the major insect molting hormone 20-hydroxyecdysone, which is secreted from the prothoracic glands. It is of steroidal structure. Insect molting hormones (ecdysone and its homologues) are generally called ecdysteroids. ...
. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence.
The pupae of different groups of insects have different names such as
''chrysalis'' for the pupae of
butterflies and ''tumbler'' for those of the
mosquito
Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ...
family. Pupae may further be enclosed in other structures such as
cocoons,
nest
A nest is a structure built for certain animals to hold eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of organic materi ...
s, or
shells.
Position in life cycle
The pupal stage follows the
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
l stage and precedes
adulthood (''
imago
In biology, the imago (Latin for "image") is the last stage an insect attains during its metamorphosis, its process of growth and development; it is also called the imaginal stage, the stage in which the insect attains maturity. It follows the f ...
'') in insects with complete metamorphosis. The pupa is a non-feeding, usually
sessile
Sessility, or sessile, may refer to:
* Sessility (motility), organisms which are not able to move about
* Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant
* Sessility (medicine), tumors and polyps that ...
stage, or highly active as in mosquitoes. It is during the pupal stage that the adult structures of the insect are formed while the larval structures are broken down. The adult structures grow from
imaginal disc
An imaginal disc is one of the parts of a holometabolous insect larva that will become a portion of the outside of the adult insect during the pupal transformation. Contained within the body of the larva, there are pairs of discs that will for ...
s.
Duration
The pupal stage may last weeks, months, or even years, depending on temperature and the species of insect. For example, the pupal stage lasts eight to fifteen days in
monarch butterflies
The monarch butterfly or simply monarch (''Danaus plexippus'') is a milkweed butterfly (subfamily Danainae) in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. ...
. The pupa may enter
dormancy or
diapause
In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press I ...
until the appropriate season to emerge as an adult insect. In
temperate
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...
climates pupae usually stay dormant during winter, while in the
tropics
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referr ...
pupae usually do so during the
dry season
The dry season is a yearly period of low rainfall, especially in the tropics. The weather in the tropics is dominated by the tropical rain belt, which moves from the northern to the southern tropics and back over the course of the year. The te ...
.
Emergence
Insects emerge (eclose) from pupae by splitting the pupal case. Most butterflies emerge in the morning. In mosquitoes, the emergence is in the evening or night. In fleas, the process is triggered by vibrations that indicate the possible presence of a suitable host. Prior to emergence, the adult inside the pupal
exoskeleton
An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton (endoskeleton) in for example, a human. In usage, some of the ...
is termed ''pharate''. Once the pharate adult has eclosed from the pupa, the empty pupal exoskeleton is called an ''
exuvia''; in most
hymenopteran
Hymenoptera is a large order of insects, comprising the 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 parasitic.
Females typica ...
s (ants, bees and wasps) the exuvia is so thin and membranous that it becomes "crumpled" as it is shed.
Pupal mating
![Mottled Emigrant (Catopsilia pyranthe) mating with emerging butterfly from pupa in Hyderabad, AP W IMG 9437](https://upload.wikimedia.org/wikipedia/commons/e/e1/Mottled_Emigrant_%28Catopsilia_pyranthe%29_mating_with_emerging_butterfly_from_pupa_in_Hyderabad%2C_AP_W_IMG_9437.jpg)
In a few taxa of the Lepidoptera, especially ''
Heliconius
''Heliconius'' comprises a colorful and widespread genus of brush-footed butterflies commonly known as the longwings or heliconians. This genus is distributed throughout the tropical and subtropical regions of the New World, from South America ...
'', pupal mating is an extreme form of reproductive strategy in which the adult male mates with a female pupa about to emerge, or with the newly moulted female; this is accompanied by other actions such as capping of the reproductive system of the female with the
sphragis, denying access to other males, or by exuding an anti-aphrodisiac pheromone.
Defense
Pupae are usually immobile and are largely defenseless. To overcome this, pupae often are covered with a cocoon, conceal themselves in the environment, or form underground. There are some species of
Lycaenid butterflies which are protected in their pupal stage by ants. Another means of defense by pupae of other species is the capability of making sounds or vibrations to scare potential predators. A few species use chemical defenses including toxic secretions. The pupae of social
hymenopterans are protected by adult members of the hive.
Types
Based on the presence or absence of articulated
mandible
In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...
s that are employed in emerging from a cocoon or pupal case, the pupae can be classified in to two types:
* Decticous pupa – a pupa with articulated mandibles. Examples are pupae of the orders
Neuroptera,
Mecoptera
Mecoptera (from the Greek: ''mecos'' = "long", ''ptera'' = "wings") is an order of insects in the superorder Endopterygota with about six hundred species in nine families worldwide. Mecopterans are sometimes called scorpionflies after their lar ...
,
Trichoptera
The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the b ...
and few
Lepidoptera families.
* Adecticous pupa – a pupa without articulated mandibles. Examples include the orders
Strepsiptera
The Strepsiptera are an order of insects with eleven extant families that include about 600 described species. They are endoparasites in other insects, such as bees, wasps, leafhoppers, silverfish, and cockroaches. Females of most species never ...
,
Coleoptera,
Hymenoptera,
Diptera and
Siphonaptera.
Based on whether the pupal appendages are free or attached to the body, the pupae can be classified as one of three types:
* Exarate pupa – appendages are free and are not usually encapsulated within a cocoon. Decticous pupae are always exarate; some adecticous pupae are as well. (Neuroptera, Trichoptera,
Cyclorrhapha
Cyclorrhapha is an unranked taxon within the infraorder Muscomorpha. They are called "Cyclorrhapha" ('circular-seamed flies') with reference to the circular aperture through which the adult escapes the puparium. This is a circumscriptional name t ...
of Dipterans, Siphonaptera, most Coleoptera, Hymenoptera, and few Lepidoptera).
* Obtect pupa – appendages are attached closely to the body and are commonly encapsulated within a cocoon. Some adecticous pupa are obtect forms. (Most Lepidoptera,
Nematocera
The Nematocera (the name means "thread-horns") are a suborder of elongated flies with thin, segmented antennae and mostly aquatic larvae. This group is paraphyletic and contains all flies but species from suborder Brachycera (the name means "sh ...
and
Brachycera
The Brachycera are a suborder of the order Diptera. It is a major suborder consisting of around 120 families. Their most distinguishing characteristic is reduced antenna segmentation.
Description
A summary of the main physical characteristics i ...
of Dipterans,
Staphylinidae and
Chrysomelidae Coleopterans, many
Chalcidoidea Hymenopterans)
* Coarctate pupa – enclosed in a hardened cuticle of the penultimate larval instar called a puparium. However, the pupa itself is of the exarate adecticous pupal form. (Cyclorrhapha of Dipterans).
Chrysalis
![Painted Lady Chrysalis micro CT](https://upload.wikimedia.org/wikipedia/commons/b/b3/Painted_Lady_Chrysalis_micro_CT.jpg)
A chrysalis ( la, chrysallis, from grc, χρυσαλλίς, , plural: , also known as an ''aurelia'') or nympha is the pupal stage of
butterflies. The term is derived from the metallic–gold coloration found in the pupae of many butterflies, referred to by the Ancient Greek term () for gold.
When the caterpillar is fully grown, it makes a button of silk which it uses to fasten its body to a leaf or a twig. Then the caterpillar's skin comes off for the final time. Under this old skin is a hard skin called a chrysalis.
Because chrysalises are often showy and are formed in the open, they are the most familiar examples of pupae. Most chrysalides are attached to a surface by a
Velcro
Velcro, officially known as Velcro IP Holdings LLC and trading as Velcro Companies, is a British privately held company, founded by Swiss electrical engineer George de Mestral in the 1950s. It is the original manufacturer of hook-and-loop fast ...
-like arrangement of a
silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...
en pad spun by the
caterpillar, usually cemented to the underside of a perch, and the ''cremastral'' hook or hooks protruding from the rear of the chrysalis or ''cremaster'' at the tip of the pupal
abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the to ...
by which the caterpillar fixes itself to the pad of silk. ( 'suspended')
Like other types of pupae, the chrysalis stage in most butterflies is one in which there is little movement. However, some butterfly pupae are capable of moving the abdominal segments to produce sounds or to scare away potential
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s. Within the chrysalis, growth and differentiation occur.
The adult butterfly emerges (ecloses) from this and expands its wings by pumping
haemolymph
Hemolymph, or haemolymph, is a fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod (invertebrate) body, remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which ...
into the wing veins. Although this sudden and rapid change from pupa to imago is often called
metamorphosis, metamorphosis is really the whole series of changes that an insect undergoes from egg to adult.
When emerging, the butterfly uses a liquid, sometimes called
cocoonase
Cocoonase is a trypsin-like proteolytic enzyme produced by silkworms (of both ''Bombyx'' and ''Antheraea'' species) as they near the final stages of their metamorphosis. It is produced by cells in the proboscis and exuded onto the galeae. Its f ...
, which softens the shell of the chrysalis. Additionally, it uses two sharp claws located on the thick joints at the base of the forewings to help make its way out. Having emerged from the chrysalis, the butterfly will usually sit on the empty shell in order to expand and harden its wings. However, if the chrysalis was near the ground (such as if it fell off from its silk pad), the butterfly would find another vertical surface to rest upon and harden its wings (such as a wall or fence).
Moth
Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...
pupae are usually dark in color and either formed in underground cells, loose in the soil, or their pupa is contained in a protective
silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...
case called a ''cocoon''. The pupa of some species such as the
hornet moth
The hornet moth or hornet clearwing (''Sesia apiformis'') is a large moth native to Europe and the Middle East and has been introduced to North America. Its protective coloration is an example of Batesian mimicry, as its similarity to a hornet ...
develop sharp ridges around the outside called adminicula that allow the pupa to move from its place of concealment inside a tree trunk when it is time for the adult to emerge.
Pupa, chrysalis, and cocoon are frequently confused, but are quite distinct from each other. The pupa is the stage between the larva and adult stages. The chrysalis generally refers to a butterfly pupa although the term may be misleading as there are some moths whose pupae resembles a chrysalis, e.g.: the plume winged moths of the family
Pterophoridae
The Pterophoridae or plume moths are a family of Lepidoptera with unusually modified wings. Though they belong to the Apoditrysia like the larger moths and the butterflies, unlike these they are tiny and were formerly included among the assemblag ...
and some
geometrid
The geometer moths are moths belonging to the family Geometridae of the insect order Lepidoptera, the moths and butterflies. Their scientific name derives from the Ancient Greek ''geo'' γεω (derivative form of or "the earth"), and ''metro ...
moths. A cocoon is a silk case that the larvae of moths, and sometimes other insects, spin around the pupa.
Cocoon
A cocoon is a casing spun of
silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...
by many
moth
Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...
s and
caterpillars, and numerous other
holometabolous
Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the superorder Endopterygota. ...
insect
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
e as a protective covering for the pupa.
Cocoons may be tough or soft, opaque or translucent, solid or meshlike, of various colors, or composed of multiple layers, depending on the type of insect larva producing it. Many moth caterpillars shed the larval hairs (
seta
In biology, setae (singular seta ; from the Latin word for " bristle") are any of a number of different bristle- or hair-like structures on living organisms.
Animal setae
Protostomes
Annelid setae are stiff bristles present on the body. ...
e) and incorporate them into the cocoon; if these are
urticating hair
Urticating hairs or urticating bristles are one of the primary defense mechanisms used by numerous plants, almost all New World tarantulas, and various lepidopteran caterpillars. ''Urtica'' is Latin for "nettle" (stinging nettles are in the genu ...
s then the cocoon is also irritating to the touch. Some larvae attach small twigs, fecal pellets or pieces of vegetation to the outside of their cocoon in an attempt to disguise it from predators. Others spin their cocoon in a concealed location—on the underside of a
leaf
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...
, in a
crevice, down near the base of a
tree trunk
In botany, the trunk (or bole) is the stem and main wooden axis of a tree, which is an important feature in tree identification, and which often differs markedly from the bottom of the trunk to the top, depending on the species. The trunk is th ...
, suspended from a twig or concealed in the
leaf litter
Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...
.
The silk in the cocoon of the
silk moth
The domestic silk moth (''Bombyx mori''), is an insect from the moth family Bombycidae. It is the closest relative of ''Bombyx mandarina'', the wild silk moth. The silkworm is the larva or caterpillar of a silk moth. It is an economically imp ...
can be unraveled to harvest silk fibre which makes this moth the most economically important of all lepidopterans. The silk moth is the only completely domesticated lepidopteran and does not exist in the wild.
Insects that pupate in a cocoon must escape from it, and they do this either by the pupa cutting its way out, or by secreting
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
s, sometimes called
cocoonase
Cocoonase is a trypsin-like proteolytic enzyme produced by silkworms (of both ''Bombyx'' and ''Antheraea'' species) as they near the final stages of their metamorphosis. It is produced by cells in the proboscis and exuded onto the galeae. Its f ...
, that soften the cocoon. Some cocoons are constructed with built-in lines of weakness along which they will tear easily from inside, or with exit holes that only allow a one-way passage out; such features facilitate the escape of the adult insect after it emerges from the pupal skin.
Puparium
Some pupae remain inside the exoskeleton of the final larval
instar
An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ...
and this last larval "shell" is called a puparium (plural, puparia). Flies of the group
Muscomorpha
The Brachyceran infraorder Muscomorpha is a large and diverse group of flies, containing the bulk of the Brachycera, and, most of the known flies. It includes a number of the most familiar flies, such as the housefly, the fruit fly, and the blo ...
have puparia, as do members of the order
Strepsiptera
The Strepsiptera are an order of insects with eleven extant families that include about 600 described species. They are endoparasites in other insects, such as bees, wasps, leafhoppers, silverfish, and cockroaches. Females of most species never ...
, and the
Hemipteran family
Aleyrodidae
Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described.
Description and taxonomy
The A ...
.
Gallery
File:Fruit Fly Pupa.jpg, Fruit fly (''Drosophila melanogaster
''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the " vinegar fly" or "pomace fly". Starting with ...
'') pupa
File:Caterpillar making cocoon2.jpg, An emperor gum moth
''Opodiphthera eucalypti'', the emperor gum moth, is a species of moth in the family Saturniidae native to Australia. This species was formerly placed in the genus ''Antheraea''.
Distribution
The emperor gum moth may inhabit all states of Aust ...
caterpillar spinning its cocoon
File:Actias luna pupa 2 sjh.JPG, Luna moth
The Luna moth (''Actias luna'') also known as the American moon moth is a Nearctic moth in the family Saturniidae, subfamily Saturniinae, a group commonly known as giant silk moths. It has lime-green colored wings and a white body. The larvae ( ...
cocoon and pupa
File:Actias luna cocoons sjh.JPG, Assortment of Luna moth cocoons
File:Actias luna emergence sjh.gif, Luna moth emerging from pupa within silk cocoon
A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in thei ...
File:Actias luna pupa sjh enhanced.JPG, Luna moth pupa removed from cocoon
File:Chrysalis5504.jpg, Chrysalis of Gulf fritillary
The Gulf fritillary or passion butterfly (''Dione vanillae'') is a bright orange butterfly in the subfamily Heliconiinae of the family Nymphalidae. That subfamily was formerly set apart as a separate family, the Heliconiidae. The Heliconiinae a ...
File:Pupation - Inachis io.jpg, Pupation of ''Aglais io
''Aglais io'', the European peacock, more commonly known simply as the peacock butterfly, is a colourful butterfly, found in Europe and temperate Asia as far east as Japan. It was formerly classified as the only member of the genus ''Inachis'' ...
''
File:Monarch Butterfly Chrysalis.JPG, Monarch butterfly chrysalis
File:Nacimiento de una Dryas iulia, Mariposario de Icod de los Vinos, Tenerife, España, 2012-12-13, DD 03.jpg, Specimen of an eclosing ''Dryas iulia
''Dryas iulia'' (often incorrectly spelled ''julia''),Lamas, G. (editor) (2004). Atlas of Neotropical Lepidoptera. Checklist: Part 4A. Hesperioidea – Papilionoidea. commonly called the Julia butterfly, Julia heliconian, the flame, or flambeau ...
'' butterfly
File:Pupae of Japanagromyza inferna Spencer in gall of Centrosema virginianum L. - ZooKeys-374-045-g005.jpg, Pupae of ''Japanagromyza inferna'', a gall fly
A gall-inducing insect is any insect that can cause the growth of galls within plants. There are several groups of insects that meet this description. They include the gall wasps, scales, gall midges, aphids, psyllids and certain species of le ...
, in gall of ''Centrosema virginianum
''Centrosema virginianum'' is known by the common names of Spurred Butterfly Pea, wild blue vine, blue bell, and wild pea. ''C. virginianum'' is a member of the family Fabaceae, it is identified by its trailing and twining vine and showy fl ...
''
File:Cabbage looper in cocoon.jpg, Pupa of cabbage looper
The cabbage looper (''Trichoplusia ni'') is a medium-sized moth in the family Noctuidae, a family commonly referred to as owlet moths. Its common name comes from its preferred host plants and distinctive crawling behavior. Cruciferous vegetable ...
File:BARON BUTTERFLY CHRYSALIS.jpg, Pupa of Baron Butterfly Euthalia aconthea
File:Papilio polytes common Mormon pupa vijayanrajapuram 03.jpg, Papilio_polytes_common_Mormon_pupa on curry leaves.
See also
*
Brood (honeybee)
*
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
*
Silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...
References
External links
Pupa photosplus species descriptions at ''Insecta.pro''
Silk worm life cycle photos
{{Authority control
Insect physiology
Insect developmental biology
Articles containing video clips