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 hereditar ...

, 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

ecdysozoa Ecdysozoa () is a group of protostome animals, including Arthropoda (insects, chelicerata, crustaceans, and myriapods), Nematoda, and several smaller phyla. They were first defined by Aguinaldo ''et al.'' in 1997, based mainly on phylogeneti ...

ns (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 gro ...

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 ...

s) have

moulted In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...

. 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, a multicellular organism, or a community of interacting populations. They usually speciali ...

s as they can often be used to identify the

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of the animal and even its sex. 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 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 uses the singular form ''exuvium'', but in the meaning "spoils, booty".

Gallery

Anyphops02.jpg, '' Anyphops'' Platypleura.jpg, Cicada '' Platypleura'' Cicada molting animated-2.gif, Accelerated view of a cicada molting Hymenopus coronatus MHNT Exuvie.jpg, Orchid mantis Euscorpion exuvia 2.jpg, Scorpion Anax imperator Exuvie MHNT Parc de la Maourine.jpg, Dragonfly '' Anax imperator'' Asclepias syriaca-Oncopeltus fasciatus-exuviae.jpg, Large milkweed bug File:Danaus plexippus emerging from chrysalis 04.jpg, Emergent monarch butterfly clinging to exuviae

References

External links

Insect anatomy Spider anatomy {{insect-anatomy-stub