biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary i ...

, exuviae are the remains of an

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 ...

and related structures that are left after ecdysozoans (including

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 pairs ...

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s and

arachnid Arachnida () is a class of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroon ...

s) have moulted. The exuviae of an animal can be important to

biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...

s as they can often be used to identify the

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of the animal and even its

sex Sex is the trait that determines whether a sexually reproducing animal or plant produces male or female gametes. Male plants and animals produce smaller mobile gametes (spermatozoa, sperm, pollen), while females produce larger ones ( ova, of ...

. As studying insects, crustaceans, or arachnids directly is not always possible, and because exuviae can be collected fairly easily, they can play an important part in helping to determine some general aspects of a species' overall

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 ...

such as distribution, sex ratio, production, and proof of breeding in a

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

. Exuviae have been suggested as a "gold standard" for insect monitoring. For instance, when monitoring dragonfly populations the presence of exuviae of a species demonstrates that the species has completed its full life cycle from egg to adult in a habitat. However, it has also been suggested that the fact that exuviae can be hard to find could lead to an underestimation of insect species compared to, for example, counting adult insects. The Latin word ''exuviae'', meaning "things stripped from a body", is found only in the plural. ''Exuvia'' is a derived singular form, although this is a

neologism A neologism Greek νέο- ''néo''(="new") and λόγος /''lógos'' meaning "speech, utterance"] is a relatively recent or isolated term, word, or phrase that may be in the process of entering common use, but that has not been fully accepted int ...

, and not attested in texts by Roman authors. A few modern works use the singular noun ''exuvium'' (e.g.). Only a single historical work by

Propertius Sextus Propertius was a Latin elegiac poet of the Augustan age. He was born around 50–45 BC in Assisium and died shortly after 15 BC. Propertius' surviving work comprises four books of ''Elegies'' ('). He was a friend of the poets Gallus a ...

uses the singular form ''exuvium'', but in the meaning "spoils, booty".

Gallery

Anyphops02.jpg, ''

Anyphops ''Anyphops'' is a genus of wall spiders that was first described by P. L. G. Benoit in 1968. Species it contains sixty-four species, found in Africa and on Saint Helena: *'' A. alticola'' (Lawrence, 1940) – South Africa *'' A. amatolae'' (Law ...

'' Platypleura.jpg, Cicada ''

Platypleura ''Platypleura'' is a genus of cicadas that occurs widely across Africa and southern Asia. Some of the South African species are remarkable for their endothermic thermoregulation that enables crepuscular signalling, an adaptation that reduces risk ...

'' Cicada molting animated-2.gif, Accelerated view of a cicada molting Hymenopus coronatus MHNT Exuvie.jpg,

Orchid mantis ''Hymenopus coronatus'' is a mantis from the tropical forests of Southeast Asia. It is known by various common names including walking flower mantis and (pink) orchid mantis. It is one of several species known as flower mantises from their resemb ...

Euscorpion exuvia 2.jpg, Scorpion Anax imperator Exuvie MHNT Parc de la Maourine.jpg, Dragonfly ''

Anax imperator The emperor dragonfly or blue emperor (''Anax imperator'') is a large species of hawker dragonfly of the family Aeshnidae, averaging in length. The generic name ''Anax'' is from the ancient Greek , "lord"; the specific epithet ''imperator'' is t ...

'' Asclepias syriaca-Oncopeltus fasciatus-exuviae.jpg,

Large milkweed bug ''Oncopeltus fasciatus'', known as the large milkweed bug, is a medium-sized hemipteran (true bug) of the family Lygaeidae.Attisano, A. (2013) Oosorption and migratory strategy of the milkweed bug,''Oncopeltus fasciatus. Animal Behaviour 86(3):65 ...

File:Danaus plexippus emerging from chrysalis 04.jpg, Emergent

monarch butterfly 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. It ...

clinging to exuviae

References

External links

Insect anatomy Spider anatomy {{insect-anatomy-stub