Orsotriaena
Encyclopedia
Orsotriaena is a genus
of butterflies
found in South Asia
, Southeast Asia
, and Australia
. It contains only one species
, Orsotriaena medus. In India
, the butterfly has historically been called the "nigger
", but it has been renamed in Australian faunal works to the socially acceptable name of smooth-eyed bushbrown.
Orsotriaena medus is a medium-sized butterfly with wingspan of 45 to 55 mm (1.8 to 2.2 in). The butterfly is dark brown above with a thin marginal pale border. The upper hindwing having a thin submarginal line. There are no eye-spots on the upper side of the wings.
Below, the butterfly has a white discal band which runs across both wings. It has five ocelli beloe (eyespots) on the undersides of the wings. In the forewing, it has two eyespots, with the anterior eyespot slightly smaller. In the hindwing, it has two ocelli on the apical region and a separate ocellus in the tornal (hindmost) region. The uppermost of the eyespots in the hindwing are greatly smaller, while the remaining two are more or less of equal sizes.
The eggs are spherical and yellowish. They are laid on the leaf blades and stems of grasses. The larva
e are spindle-shaped, transversely wrinkled, and covered in small tubercles, giving it a rough appearance. Two long brown spines on the head point forward, while a pair of pinkish prongs project from the anal segment. The colour above is rosy-red with a blue dorsal and a white lateral line, below which, the underparts are green.
The pupa
e are perpendicularly suspended, slender and regular, except that the head-case is produced into a long beak formed of two thin processes like split straws. The colour is whitish brown to yellow, with faint bands of a darker shades. It resembles a large grain of barley or a tiny banana.
Orsotriaena medus superficially resemble members of the genus Mycalesis
(bushbrowns), but can readily be identified by the number of spots.
, Sri Lanka
, Myanmar
, Thailand
, South Yunnan
, Malaysia, the Indonesia
n archipelago, the Philippines
, New Guinea
, New Britain
and Australia
.
In India
, the butterfly occurs in South India
, Punjab
, Uttar Pradesh
, Bihar
, West Bengal
, Sikkim
, Assam
, Nagaland
, the Andaman
and Nicobar islands
.
O. medus is very common in grassy habitats up to an altitude of 1600 m (5,249.3 ft). A shy, weak-flying insect, it stays low amongst the undergrowth, and when disturbed flies for a short distance before settling down. The butterfly basks in the sun, often with its body aligned parallel to the sun's rays.
(the browns) of the brush-footed butterfly family Nymphalidae
. Orsotriaena medus is divided into several subspecies
, listed below with their respective synonyms
and geographical ranges.
es, including rice plants (Oryza sativa
), sugarcanes (Saccharum officinarum), and para grass (Brachiaria mutica). They are predominantly crepuscular
, but can sometimes be active during daytime.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
found in South Asia
South Asia
South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...
, Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. It contains only one species
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
, Orsotriaena medus. In India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, the butterfly has historically been called the "nigger
Nigger
Nigger is a noun in the English language, most notable for its usage in a pejorative context to refer to black people , and also as an informal slang term, among other contexts. It is a common ethnic slur...
", but it has been renamed in Australian faunal works to the socially acceptable name of smooth-eyed bushbrown.
Description
Below, the butterfly has a white discal band which runs across both wings. It has five ocelli beloe (eyespots) on the undersides of the wings. In the forewing, it has two eyespots, with the anterior eyespot slightly smaller. In the hindwing, it has two ocelli on the apical region and a separate ocellus in the tornal (hindmost) region. The uppermost of the eyespots in the hindwing are greatly smaller, while the remaining two are more or less of equal sizes.
The eggs are spherical and yellowish. They are laid on the leaf blades and stems of grasses. The larva
Larva
A larva 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 are spindle-shaped, transversely wrinkled, and covered in small tubercles, giving it a rough appearance. Two long brown spines on the head point forward, while a pair of pinkish prongs project from the anal segment. The colour above is rosy-red with a blue dorsal and a white lateral line, below which, the underparts are green.
The pupa
Pupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
e are perpendicularly suspended, slender and regular, except that the head-case is produced into a long beak formed of two thin processes like split straws. The colour is whitish brown to yellow, with faint bands of a darker shades. It resembles a large grain of barley or a tiny banana.
Orsotriaena medus superficially resemble members of the genus Mycalesis
Mycalesis
The bushbrowns, Mycalesis, are a genus of brush-footed butterflies. They are common in the warm regions from Central Asia to Australia, and have a high diversity in South Asia and the Wallacea....
(bushbrowns), but can readily be identified by the number of spots.
Distribution and habitat
Orsotriaena medus is native to IndiaIndia
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, Myanmar
Myanmar
Burma , officially the Republic of the Union of Myanmar , is a country in Southeast Asia. Burma is bordered by China on the northeast, Laos on the east, Thailand on the southeast, Bangladesh on the west, India on the northwest, the Bay of Bengal to the southwest, and the Andaman Sea on the south....
, Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
, South Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
, Malaysia, the Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
n archipelago, the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, New Britain
New Britain
New Britain, or Niu Briten, is the largest island in the Bismarck Archipelago of Papua New Guinea. It is separated from the island of New Guinea by the Dampier and Vitiaz Straits and from New Ireland by St. George's Channel...
and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
.
In India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, the butterfly occurs in South India
South India
South India is the area encompassing India's states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu as well as the union territories of Lakshadweep and Pondicherry, occupying 19.31% of India's area...
, Punjab
Punjab (India)
Punjab ) is a state in the northwest of the Republic of India, forming part of the larger Punjab region. The state is bordered by the Indian states of Himachal Pradesh to the east, Haryana to the south and southeast and Rajasthan to the southwest as well as the Pakistani province of Punjab to the...
, Uttar Pradesh
Uttar Pradesh
Uttar Pradesh abbreviation U.P. , is a state located in the northern part of India. With a population of over 200 million people, it is India's most populous state, as well as the world's most populous sub-national entity...
, Bihar
Bihar
Bihar is a state in eastern India. It is the 12th largest state in terms of geographical size at and 3rd largest by population. Almost 58% of Biharis are below the age of 25, which is the highest proportion in India....
, West Bengal
West Bengal
West Bengal is a state in the eastern region of India and is the nation's fourth-most populous. It is also the seventh-most populous sub-national entity in the world, with over 91 million inhabitants. A major agricultural producer, West Bengal is the sixth-largest contributor to India's GDP...
, Sikkim
Sikkim
Sikkim is a landlocked Indian state nestled in the Himalayan mountains...
, Assam
Assam
Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...
, Nagaland
Nagaland
Nagaland is a state in the far north-eastern part of India. It borders the state of Assam to the west, Arunachal Pradesh and part of Assam to the north, Burma to the east and Manipur to the south. The state capital is Kohima, and the largest city is Dimapur...
, the Andaman
Andaman Islands
The Andaman Islands are a group of Indian Ocean archipelagic islands in the Bay of Bengal between India to the west, and Burma , to the north and east...
and Nicobar islands
Nicobar Islands
The Nicobar Islands are an archipelagic island chain in the eastern Indian Ocean...
.
O. medus is very common in grassy habitats up to an altitude of 1600 m (5,249.3 ft). A shy, weak-flying insect, it stays low amongst the undergrowth, and when disturbed flies for a short distance before settling down. The butterfly basks in the sun, often with its body aligned parallel to the sun's rays.
Taxonomy
Orsotriaena medus is classified under the subfamily SatyrinaeSatyrinae
Satyrinae, the satyrines or satyrids, commonly known as the Browns, is a subfamily of the Nymphalidae . They were formerly considered a distinct family, Satyridae. This group contains nearly half of the known diversity of brush-footed butterflies...
(the browns) of the brush-footed butterfly family Nymphalidae
Nymphalidae
The Nymphalidae is a family of about 5,000 species of butterflies which are distributed throughout most of the world. These are usually medium sized to large butterflies. Most species have a reduced pair of forelegs and many hold their colourful wings flat when resting. They are also called...
. Orsotriaena medus is divided into several subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, listed below with their respective synonyms
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
and geographical ranges.
- Orsotriaena Wallengren, 1858
-
- syn. Orstriaena Young, 1903; Orsotrioena Bingham, 1905
- Orsotriaena medus (Fabricius, 1775)
- syn. Papilio medus Fabricius, 1775; Mycalesis mandosa Butler, 1868
- Orsotriaena medus cinerea (Butler, 1867) - SundalandSundalandSundaland is a biogeographical region of Southeastern Asia which encompasses the areas of the Asian continental shelf that was exposed during the last ice age. It included the Malay Peninsula on the Asian mainland, as well as the large islands of Borneo, Java, and Sumatra and their surrounding...
.
-
- syn. Mycalesis cinerea Butler, 1867
- Orsotriaena medus jopas (Hewitson, 1864) - North SulawesiSulawesiSulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
.
-
- syn. Mycalesis jopas Hewitson, 1864
- Orsotriaena medus mandata (Moore, 1857) - Sri LankaSri LankaSri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, South IndiaSouth IndiaSouth India is the area encompassing India's states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu as well as the union territories of Lakshadweep and Pondicherry, occupying 19.31% of India's area...
.
-
- syn. Mycalesis mandata Moore, 1857
- Orsotriaena medus medus (Fabricius, 1775) - N. India to Thailand, Timor, the PhilippinesPhilippinesThe Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, Papua New GuineaPapua New GuineaPapua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
, South YunnanYunnanYunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
.
-
- syn. Papilio hesione Cramer, 1775; Papilio doris Stoll, 1781; Mycalesis runeka Moore, 1857
- Orsotriaena medus mendice (Fruhstorfer, 1911) - South SulawesiSulawesiSulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
.
-
- syn. Orsotriaena mendice Fruhstorfer 1911
- Orsotriaena medus moira (Waterhouse & Lyell, 1914) - Banks Island, Darnley Island, Cape York.
-
- syn. Orsotriaena moira Waterhouse & Lyell, 1914
- Orsotriaena medus mutata (Butler, 1875) - New BritainNew BritainNew Britain, or Niu Briten, is the largest island in the Bismarck Archipelago of Papua New Guinea. It is separated from the island of New Guinea by the Dampier and Vitiaz Straits and from New Ireland by St. George's Channel...
.
-
- syn. Orsotriaena mutata Butler, 1875
- Orsotriaena medus paupercula (Fruhstorfer, 1908) - Sula IslandsSula IslandsThe Sula Islands are a group of islands in North Maluku in Indonesia. Its three main islands are Mangole, Sanae and Taliabu, with smaller islands Lifamatola and Seho. It is administered as Kepulauan Sula Regency...
.
-
- syn. Orsotriaena paupercula Fruhstorfer, 1908
- Orsotriaena medus zipoetina (Fruhstorfer, 1908) - SumatraSumatraSumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
-
- syn. Orsotriaena zipoetina Fruhstorfer, 1908
- Orsotriaena medus cinerea (Butler, 1867) - Sundaland
- syn. Orstriaena Young, 1903; Orsotrioena Bingham, 1905
Ecology and behavior
The larvae feed on grassGrass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
es, including rice plants (Oryza sativa
Oryza sativa
Oryza sativa, commonly known as Asian rice, is the plant species most commonly referred to in English as rice. Oryza sativa is the cereal with the smallest genome, consisting of just 430Mb across 12 chromosomes...
), sugarcanes (Saccharum officinarum), and para grass (Brachiaria mutica). They are predominantly crepuscular
Crepuscular
Crepuscular animals are those that are active primarily during twilight, that is during dawn and dusk. The word is derived from the Latin word crepusculum, meaning "twilight." Crepuscular is, thus, in contrast with diurnal and nocturnal behavior. Crepuscular animals may also be active on a bright...
, but can sometimes be active during daytime.