''Orthonama obstipata'', the gem, is a

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 ...

of the family

Geometridae 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 ...

. The species was first described by

Johan Christian Fabricius Johan Christian Fabricius (7 January 1745 – 3 March 1808) was a Danish zoologist, specialising in "Insecta", which at that time included all arthropods: insects, arachnids, crustaceans and others. He was a student of Carl Linnaeus, and is co ...

in 1794. It is a

cosmopolitan species In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The extr ...

. In continental Europe though in the northeast, its range does not significantly extend beyond the Baltic region and it is absent from northern

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...

. This well-flying species is prone to vagrancy and able to cross considerable distances of open sea; it can thus be regularly found on the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...

(though mainly in the south) and even on

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...

. Under its junior synonyms ''Nycterosea brunneipennis'' and ''Geometra fluviata'', the gem is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

of genera ''Nycterosea'' and ''Percnoptilota'', respectively. The latter is treated as junior synonym of the former, but ''Nycterosea'', though usually included in ''Orthonama'' these days, may warrant recognition as an independent genus after all.

Description and ecology

The adult's

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

is ; in their core range (e.g.

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...

and the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

) they can be seen between April and November, but in outlying regions they may only be regularly encountered in late summer and early autumn, when vagrant individuals abound. This species is strongly

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

: Males are light brown with a wavy pattern of whitish lines and a broad darker band running across the wings, forming concentric semicircles when the moth is at rest. There is a small whitish-rimmed black spot within the darker band between the centre and the leading edge of each forewing. The females are slightly larger and much darker, almost uniformly blackish brown with an indistinct lighter pattern and a forewing spot like the males have. The Gem - Hodges-7414 (Orthonama obstipata)

The Gem - Hodges-7414 (Orthonama obstipata)

Adult caterpillars are greenish or brownish coloured and slightly tapered towards the head. The sides are yellowish, from the middle body segments light, dark-lined diamond spots which are black cored stand out

Similar species

Due to the very characteristic wing drawing, the female moths are unmistakable. In the males there is a distant resemblance to grey-brown specimens of ''

Xanthorhoe designata ''Xanthorhoe designata'', the flame carpet, is a moth of the genus '' Xanthorhoe'' in the family Geometridae. The species was first described by Johann Siegfried Hufnagel in 1767. Distribution It is found in Europe, Asiatic Russia and Japan. ...

''. In ''X. designata'' the midfield is, though, predominantly reddish-brown and bounded by a narrow black band.

Biology

The caterpillar

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 feed on a wide range of low-growing

core eudicots The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons. Traditionally they were called tricolpates or non-magnoliid dicots ...

, but prefer

asterid In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flo ...

s. Host plants recorded from the

Central Europe Central Europe is an area of Europe between Western Europe and Eastern Europe, based on a common historical, social and cultural identity. The Thirty Years' War (1618–1648) between Catholicism and Protestantism significantly shaped the a ...

an part of its range include:

Euasterids I In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total floweri ...

Gentianales Gentianales is an order of flowering plants, included within the asterid clade of eudicots. It comprises more than 20,000 species in about 1,200 genera in 5 families. More than 80% of the species in this order belong to the family Rubiaceae. Man ...

Rubiaceae The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with interpetiolar stipules a ...

** ''

Galium ''Galium'' is a large genus of annual and perennial herbaceous plants in the family Rubiaceae, occurring in the temperate zones of both the Northern and Southern Hemispheres. Some species are informally known as bedstraw. There are over 600 spe ...

'' (bedstraws) *

Solanales The Solanales are an order of flowering plants, included in the asterid group of dicotyledons. Some older sources used the name Polemoniales for this order. Taxonomy Under the older Cronquist system, the latter three families were placed elsewh ...

Convolvulaceae Convolvulaceae (), commonly called the bindweeds or morning glories, is a family of about 60 genera and more than 1,650 species. These species are primarily herbaceous vines, but also include trees, shrubs and herbs. The tubers of several spe ...

** ''

Convolvulus ''Convolvulus'' is a genus of about 200 to 250''Convolvulus''.
Flora of China.

'' (true bindweeds)

Euasterids II In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total floweri ...

Asterales Asterales () is an order of dicotyledonous flowering plants that includes the large family Asteraceae (or Compositae) known for composite flowers made of florets, and ten families related to the Asteraceae. While asterids in general are charact ...

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

** '' Anthemis'' (dog-fennels) ** '' Chrysanthemum'' (chrysanthemums) ** ''

Eupatorium ''Eupatorium'' is a genus of flowering plants in the family Asteraceae, containing from 36 to 60 species depending on the classification system. Most are herbaceous perennials growing to tall. A few are shrubs. The genus is native to temperat ...

'' (bonesets) ** ''

Senecio ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Mor ...

'' (ragworts and groundsels) – e.g.

common groundsel ''Senecio vulgaris'', often known by the common names groundsel and old-man-in-the-spring, is a flowering plant in the family Asteraceae. It is an annual herb, native to Europe and widely naturalised as a ruderal species in suitable disturbed ha ...

(''S. vulgaris'') in the

Eurosids II The rosids are members of a large clade ( monophyletic group) of flowering plants, containing about 70,000 species, more than a quarter of all angiosperms. The clade is divided into 16 to 20 orders, depending upon circumscription and classific ...

Brassicales The Brassicales (or Cruciales) are an order of flowering plants, belonging to the eurosids II group of dicotyledons under the APG II system. One character common to many members of the order is the production of glucosinolate (mustard oil) compo ...

Brassicaceae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The leav ...

** ''

Alyssum ''Alyssum'' is a genus of over a hundred species of flowering plants in the family Brassicaceae, native to Europe, Asia, and northern Africa, with the highest species diversity in the Mediterranean region. The genus comprises annual and perenni ...

'' (alyssums) ** '' Nasturtium'' (watercresses) Basal core eudicots *

Caryophyllales Caryophyllales ( ) is a diverse and heterogeneous order of flowering plants that includes the cacti, carnations, amaranths, ice plants, beets, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves. The betalai ...

Polygonaceae The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus '' Polygonum'', and was first used by Antoine Laurent de Jussieu in 1 ...

** ''

Polygonum ''Polygonum'' is a genus of about 130 species of flowering plant in the buckwheat and knotweed family Polygonaceae. Common names include knotweed and knotgrass (though the common names may refer more broadly to plants from Polygonaceae). In the ...

'' (knotweed) ** '' Rumex'' (docks and sorrels)

Synonyms

The widespread, strongly

and somewhat

phenotypical In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological prop ...

ly variable gem has been described anew time and again by various authors, even as late as the early 20th century, but all these supposedly distinct

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

are nowadays considered to refer to a single species. Junior synonyms of the gem include:Pitkin & Jenkins (2004ab), and see references in Savela (2002)

Footnotes

References

* (1942)
"Seltsame Geometridenfunde"
eculiar records of geometer moths ''Zeitschrift des Wiener Entomologen-Vereins''. 27: 109.
"70.047 BF1720 The Gem ''Nycterosea obstipata'' (Fabricius, 1794)"
Retrieved May 15, 2019. * * *

External links

''Nycterosea obstipata'' on ''Fauna Europaea''''Lepiforum e.V.''''Nycterosea obstipata'' on ''De Vlinderstichting''
{{DEFAULTSORT:Orthonama Obstipata Xanthorhoini Moths of Europe Moths of Cape Verde Moths of Africa Moths of Iceland Moths of Japan Moths described in 1794 Taxa named by Johan Christian Fabricius