Amyna axis
Encyclopedia
The Eight-Spot is a moth
of the Noctuidae
family.
, India
, Indonesia
. Australia
and the Cook Islands
.
The moth migrates
north each year in late summer and fall. It is common in southern North America
, from Florida
to Arizona
. It is a regular migrant to the mid-eastern states, and rarely as far as Wisconsin
, Ontario
and Quebec
.
Adults are on wing from August to October.
, Celosia
, Digera, Helianthus
, Chenopodium
, Spinacia
, Ipomoea
, Ricinus, Arachis
, Crotalaria
, Medicago
, Phaseolus
, Hibiscus
, Cardiospermum
, Solanum
, Corchorus
and Parasponia species.
It is an irregular minor pest worldwide of mung bean
s (Vigna radiata), black-eyed peas
(Vigna unguiclata), lucerne
(Medicago sativa) and soy beans (Glycine max). Their prevalence may be under-reported due to the resemblance of the caterpillar with those of Chrysoieixis species.
Larvae perch on the undersides of leaves and along stems and petioles. At rest, the abdominal segments are often looped upward. When alarmed the larva essentially jumps from the host and continues to wreathe and wriggle wildly. Prepupal larvae take on a pinkish cast. Pupation occurs in a silken cocoon below (usually) or at the soil surface. Sand and/or plant debris are interwoven into the cocoon wall.
of 20-25 mm. The forewings have faint greyish-white lines and an obscure figure-of-eight mark on it. The hindwings are lighter with fainter markings. The male can be differentiated by the presence of a small semi-transparent patch on each wing.
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
of the Noctuidae
Noctuidae
The Noctuidae or owlet moths are a family of robustly-built moths that includes more than 35,000 known species out of possibly 100,000 total, in more than 4,200 genera. They constitute the largest family in the Lepidoptera....
family.
Distribution
It is found in the tropics and subtropics worldwide, and occurs in AfricaAfrica
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, 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...
, 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...
. 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...
and the Cook Islands
Cook Islands
The Cook Islands is a self-governing parliamentary democracy in the South Pacific Ocean in free association with New Zealand...
.
The moth migrates
Lepidoptera migration
Lepidoptera migration is a biological phenomenon whereby populations of butterflies or moths migrate over long distances to areas where they cannot settle for long periods of time...
north each year in late summer and fall. It is common in southern North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, from Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
to Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
. It is a regular migrant to the mid-eastern states, and rarely as far as Wisconsin
Wisconsin
Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
and Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
.
Adults are on wing from August to October.
Food plants
The larvae feed on Amaranthus, CrotonCroton (genus)
Croton is an extensive flowering plant genus in the spurge family, Euphorbiaceae, established by Carl Linnaeus in 1737. The plants of this genus were described and introduced to Europeans by Georg Eberhard Rumphius. The common names for this genus are rushfoil and croton, but the latter also...
, Celosia
Celosia
Celosia is a small genus of edible and ornamental plants in the amaranth family, Amaranthaceae. The generic name is derived from the Greek word κηλος , meaning "burned," and refers to the flame-like flower heads. Species are commonly known as woolflowers, or, if the flower heads are crested by...
, Digera, Helianthus
Helianthus
Helianthus L. is a genus of plants comprising 52 species in the Asteraceae family, all of which are native to North America, with some species Helianthus L. is a genus of plants comprising 52 species in the Asteraceae family, all of which are native to North America, with some species Helianthus...
, Chenopodium
Chenopodium
Chenopodium is a genus of about 150 species of perennial or annual herbaceous flowering plants known as the goosefoots, which occur almost anywhere in the world. It is placed in the family Amaranthaceae in the APG II system; older classifications separate it and its relatives as Chenopodiaceae, but...
, Spinacia
Spinacia
Spinacia is the spinach genus.-External links:*...
, Ipomoea
Ipomoea
Ipomoea is the largest genus in the flowering plant family Convolvulaceae, with over 500 species. Most of these are called "morning glories", but this can refer to related genera also. Those formerly separated in Calonyction are called "moonflowers"...
, Ricinus, Arachis
Arachis
Arachis is a genus of about 70 species of annual and perennial flowering plants in the pea family , native to South America. At least one species, the peanut , is a major food crop species of global importance; some of the other species are cultivated for food to a small extent in South America....
, Crotalaria
Crotalaria
Crotalaria is a genus of herbaceous plants and woody shrubs in the Family Fabaceae commonly known as rattlepods. Some 600 or more species of Crotalaria are described worldwide, mostly from the tropics; at least 500 species are known from Africa. Some species of Crotalaria are grown as ornamentals...
, Medicago
Medicago
Medicago is a genus of flowering plants, commonly known as medick or burclover. The name is based on Latin medica 'alfalfa, lucerne,' from 'Median .'...
, Phaseolus
Phaseolus
Phaseolus is a genus in the family Fabaceae of about fifty plant species, all native to the Americas.At least four of the species have been domesticated since pre-Columbian times for their beans. Most prominent among these is the common bean, P...
, Hibiscus
Hibiscus
Hibiscus is a genus of flowering plants in the mallow family, Malvaceae. It is quite large, containing several hundred species that are native to warm-temperate, subtropical and tropical regions throughout the world...
, Cardiospermum
Cardiospermum
Cardiospermum is a genus of approximately 14 species in the soapberry family, Sapindaceae, which are native to the American, Indian, and African tropics...
, Solanum
Solanum
Solanum, the nightshades, horsenettles and relatives, is a large and diverse genus of annual and perennial plants. They grow as forbs, vines, subshrubs, shrubs, and small trees, and often have attractive fruit and flowers. Many formerly independent genera like Lycopersicon or Cyphomandra are...
, Corchorus
Corchorus
Corchorus is a genus of about 40-100 species of flowering plants in the family Malvaceae, native to tropical and subtropical regions throughout the world....
and Parasponia species.
It is an irregular minor pest worldwide of mung bean
Mung bean
The mung bean is the seed of Vigna radiata. It is native to the Indian subcontinent.-Description:They are small, ovoid in shape, and green in color...
s (Vigna radiata), black-eyed peas
Cowpea
The Cowpea is one of several species of the widely cultivated genus Vigna. Four cultivated subspecies are recognised:*Vigna unguiculata subsp. cylindrica Catjang...
(Vigna unguiclata), lucerne
Lucerne
Lucerne is a city in north-central Switzerland, in the German-speaking portion of that country. Lucerne is the capital of the Canton of Lucerne and the capital of the district of the same name. With a population of about 76,200 people, Lucerne is the most populous city in Central Switzerland, and...
(Medicago sativa) and soy beans (Glycine max). Their prevalence may be under-reported due to the resemblance of the caterpillar with those of Chrysoieixis species.
Early stages
The larva are thin-bodied have faint white stripes and two pairs of ventral pro-legs. At low densities caterpillars are pale green. Among caterpillars at high densities there are higher frequencies of melanistic phenotypes. The degree of blackening varied widely, ranging from individuals with simple subdorsal-lateral patches to those that were mostly black.Larvae perch on the undersides of leaves and along stems and petioles. At rest, the abdominal segments are often looped upward. When alarmed the larva essentially jumps from the host and continues to wreathe and wriggle wildly. Prepupal larvae take on a pinkish cast. Pupation occurs in a silken cocoon below (usually) or at the soil surface. Sand and/or plant debris are interwoven into the cocoon wall.
Adult
The adult moth is chocolate brown above and has a wingspanWingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...
of 20-25 mm. The forewings have faint greyish-white lines and an obscure figure-of-eight mark on it. The hindwings are lighter with fainter markings. The male can be differentiated by the presence of a small semi-transparent patch on each wing.