Overview

''Aglia tau'', the tau emperor, is a

moth Moths are a group of insects that includes all members of the order Lepidoptera that are not Butterfly, butterflies. They were previously classified as suborder Heterocera, but the group is Paraphyly, paraphyletic with respect to butterflies (s ...

of the family

Saturniidae Saturniidae, members of which are commonly named the saturniids, is a family of Lepidoptera with an estimated 2,300 described species. The family contains some of the largest species of moths in the world. Notable members include the emperor m ...

. They are also known as giant silkmoths. It is found in Europe and across

Central Asia Central Asia is a region of Asia consisting of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. The countries as a group are also colloquially referred to as the "-stans" as all have names ending with the Persian language, Pers ...

to the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

coast. The species was first described by

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

in his 1758 10th edition of ''Systema Naturae''. Their genus, '' Aglia'', is composed of 6 Palearctic (North European) species.

Size

The

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the opposite wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingsp ...

is 60–84 mm. The moth flies from March to July with a univoltine lifecycle depending on the location. ;''Aglia tau'' Aglia tau MHNT Male Dos.jpg, ♂ Aglia tau MHNT Male ventre.jpg, ♂ △ Aglia tau Femelle dos.jpg, ♀ Aglia tau Femelle ventre.jpg, ♀ △ ; ''Aglia tau ''f.'' melaina'' Aglia tau f. melaina - Moravia Czech Republic - male dorsal.jpg, ♂ Aglia tau f. melaina - Moravia Czech Republic - male ventral.jpg, ♂ △ (MHNT) Aglia tau f. melaina - Moravia Czech Republic - female dorsal.jpg, ♀ (MHNT) Aglia tau f. melaina - Moravia Czech Republic - female ventral.jpg, ♀ △

Habitat

The larvae primarily feed on

European beech ''Fagus sylvatica'', the European beech or common beech, is a large, graceful deciduous tree in the beech family with smooth silvery-gray bark, large leaf area, and a short trunk with low branches. Description ''Fagus sylvatica'' is a large ...

, but also

birch A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 3 ...

, ''

Alnus glutinosa ''Alnus glutinosa'', the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family (biology), family Betulaceae, native plant, native to most of Europe, southwest Asia and northern Africa. ...

'', ''

Salix caprea ''Salix caprea'', known as goat willow, pussy willow or great sallow, is a common species of willow native to Europe and western and central Asia.Meikle, R. D. (1984). ''Willows and Poplars of Great Britain and Ireland''. BSBI Handbook 4. . De ...

'' and ''

Sorbus aucuparia ''Sorbus aucuparia'', commonly called rowan (, also ) and mountain-ash, is a species of deciduous tree or shrub in the rose family. The tree has a slender trunk with smooth bark, a loose and roundish crown, and its leaves are pinnate in pairs o ...

''. The larvae look similar to Royal Walnut Moth caterpillars '' Citheronia regalis'' in their earlier instars. They can be found in older growth forests, with a large portion of trees in the ''

Fagaceae The Fagaceae (; ) are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with around 1,000 or more species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species ...

'' family. They can also be found in younger riparian forests with less ''

'' species present.

Lifecycle

Their life cycle is similar to any ''

Lepidopterans Lepidoptera ( ) or lepidopterans is an order (biology), order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organ ...

'', consisting of 4 stages. Eggs laid by adult females take about 3 weeks to hatch into first

instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...

caterpillars. These grow quickly and go through 4 more instars, for 5 total. Then they pupate on the forest floor. These pupae will overwinter until March, until warmer weather comes and they start developing. Adult moths lack a mouth and only breed. The adult females lay eggs then die. File:Aglia Tau larva's 4th instar.JPG, 4th instar larva of the Tau Emporer File:Aglia tau IMG 0982.jpg, Adult male, ventral view

References

External links

Moths and ''Butterflies of Europe and North Africa''''Lepiforum e.V.''''Vlindernet.nl''
Agliinae Moths described in 1758 Moths of Asia Moths of Europe Taxa named by Carl Linnaeus {{Saturniidae-stub