Ceylon tree nymph | |
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Specimen collected by Robert Templeton | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Lepidoptera |
Family: | Nymphalidae |
Genus: | Idea |
Species: | I. iasonia |
Binomial name | |
Idea iasonia (Westwood, 1848) | |
Synonyms | |
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The Ceylon tree nymph (Idea iasonia) is a species of nymphalid butterfly in the subfamily Danainae. It is endemic to Sri Lanka. First described by John Westwood in 1848, the Ceylon tree nymph can be found in both wet and dry zones of Sri Lanka. It is the largest member of the family Danaidae in that country. It is listed as a near threatened species in the IUCN Red List.
The species was first described by English entomologist John O. Westwood in 1848, as Hestia iasonia. For several years it was considered to be only an island race of I. lynceus , a species found in eastern Asia. However the two species have differences in their wing shapes and in the male genitalia. It is of the genus Idea, and belongs to the subfamily Danainae of the family Nymphalidae. Its binomial name is Idea iasonia. [2]
The Ceylon tree nymph has a wingspan of 110–155 mm, making it the largest member of the family Danaidae in Sri Lanka. [3] Both its wings have similar patterns and colouration. The wings are of a translucent silvery-white colour. The forewings are almost twice as long as their width. The female is larger than the male, and the males have narrower forewings than the females. [3] The surface area of the Ceylon tree nymph's wings is relatively large when compared with its weight; this allows it to fly with little effort and stay aloft for long periods of time. [4] Ceylon tree nymphs from the dry zone of the country are usually larger in size and lighter in colour than ones from the wet zone. [3]
The species is endemic to Sri Lanka. There are two populations of the Ceylon tree nymph. The smaller and darker variety is found in the wet zone of Sri Lanka from sea level to about 5,000 feet (1,500 m). [2] They usually inhabit the sub-canopies of lowland tropical rain forests. [5]
The other variety, which is larger and lighter coloured, is found in the low country dry zone. They are usually encountered near water courses. [2]
Since the Ceylon tree nymph requires very little effort to fly, its wing beats are very slow, so slow that the individual movements of each wing can be easily observed. [3] Most of its time is spent flying and hovering in the high tree canopies. However, it descends to ground level to feed and to breed, [4] but does not rest on the ground. [3] It usually rests on the ends of dead branches or twigs. [3]
Mating occurs at ground level and the male and female fly together for an hour or more before mating. [3] The male releases pheromones and other chemicals from its hair-pencils to stimulate the female. These include danaidone, a poisonous substance that helps to protect it from predators, which is later passed on to the eggs. [4]
The early stages of life of the Ceylon tree nymph are not well recorded. One account by naturalists Lionel de Nicéville and N. Manders dating from about 1900 describes the larva as "velvety black with four pairs of long filamentous tentacles" with each segment of its body marked with a pale yellow band. The record further mentions that it has twelve segments and that the sixth segment has a "large oval crimson spot". Its head and legs are black. [2]
In the IUCN Red List, the Ceylon tree nymph is listed as lower risk/near threatened. [6] The main threat faced by the Ceylon tree nymph is the destruction of its habitat. However, various direct steps have been taken for the conservation of this species. Several of its naturally occurring areas are protected areas, such as the forest reserve of Sinharaja. [4]
A common classification of the Lepidoptera involves their differentiation into butterflies and moths. Butterflies are a natural monophyletic group, often given the suborder Rhopalocera, which includes Papilionoidea, Hesperiidae (skippers), and Hedylidae. In this taxonomic scheme, moths belong to the suborder Heterocera. Other taxonomic schemes have been proposed, the most common putting the butterflies into the suborder Ditrysia and then the "superfamily" Papilionoidea and ignoring a classification for moths.
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies but are usually smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Late Jurassic, and are found on every continent except Antarctica.
The Sri Lanka frogmouth, Sri Lankan frogmouth or Ceylon frogmouth is a small frogmouth found in the Western Ghats of south India and Sri Lanka. Related to the nightjars, it is nocturnal and is found in forest habitats. The plumage coloration resembles that of dried leaves and the bird roosts quietly on branches, making it difficult to see. Each has a favourite roost that it uses regularly unless disturbed. It has a distinctive call that is usually heard at dawn and dusk. The sexes differ slightly in plumage.
The grizzled giant squirrel is a large tree squirrel in the genus Ratufa found in the highlands of the Central and Uva provinces of Sri Lanka, and in patches of riparian forest along the Kaveri River and in the hill forests of Karnataka, Tamil Nadu and Kerala states of southern India. The International Union for Conservation of Nature (IUCN) lists the species as near threatened due to habitat loss and hunting.
Euploea core, also known as the common crow, is a common butterfly found in South Asia to Australia. In India it is also sometimes referred to as the common Indian crow, and in Australia as the Australian crow. It belongs to the crows and tigers subfamily Danainae.
Delias eucharis, the common Jezebel, is a medium-sized pierid butterfly found in many areas of south and southeast Asia, especially in the non-arid regions of India, Bangladesh, Sri Lanka, Indonesia, Myanmar and Thailand. The common Jezebel is one of the most common of the approximately 225 described species in the genus Delias.
Abisara echerius, the plum Judy, is a small but striking butterfly found in Asia belonging to the Punches and Judies family (Riodinidae). It is difficult to distinguish it from Abisara bifasciata.
Papilio polytes, the common Mormon, is a common species of swallowtail butterfly widely distributed across Asia.
Graphium sarpedon, the common bluebottle or blue triangle in Australia, is a species of swallowtail butterfly that is found in East, South and Southeast Asia, as well as eastern Australia. There are approximately sixteen subspecies with differing geographical distributions.
Danaus chrysippus, also known as the plain tiger, African queen, or African monarch, is a medium-sized butterfly widespread in Asia, Australia and Africa. It belongs to the Danainae subfamily of the brush-footed butterfly family Nymphalidae. Danainae primarily consume plants in the genus Asclepias, more commonly called milkweed. Milkweed contains toxic compounds, cardenolides, which are often consumed and stored by many butterflies. Because of their emetic properties, the plain tiger is unpalatable to most predators. As a result, its colouration is widely mimicked by other species of butterflies. The plain tiger inhabits a wide variety of habitats, although it is less likely to thrive in jungle-like conditions and is most often found in drier, wide-open areas.
Graphium nomius, the spot swordtail, is a butterfly found in South and Southeast Asia that belongs to the swallowtail family. The species was first described by Eugenius Johann Christoph Esper in 1793. One of the grandest sights is a host of spot swordtails mud-puddling or swarming around a flowering forest tree.
Pachliopta aristolochiae, the common rose, is a species of swallowtail butterfly belonging to the genus Pachliopta, the roses, or red-bodied swallowtails. It is a common butterfly which is extensively distributed across south and southeast Asia.
Belenois aurota, the pioneer or pioneer white or caper white, is a small to medium-sized butterfly of the family Pieridae, that is, the yellows and whites, which is found in South Asia and Africa. In Africa, it is also known as the brown-veined white, and is well known during summer and autumn when large numbers migrate north-east over the interior.
Parantica nilgiriensis, the Nilgiri tiger, is a butterfly found in the Western Ghats of India south of the Konkan. It belongs to the danaid group of the brush-footed butterflies family.
Idea is a genus of butterflies known as tree nymphs or paper butterflies. The member species are concentrated around South-East Asia. See Sevenia for the genus of African tree nymphs. These slender butterflies have very large, papery white wings with black veins and markings. They stay high up in the treetops where they flap around in slow flight. Like most other monarch butterflies, wood nymphs are poisonous, and the striking colour patterns signal this. Several butterflies from other groups mimic these patterns.
Troides darsius, the Sri Lankan birdwing, is a species of birdwing butterfly found in Sri Lanka. It is the largest butterfly on the island and is also the national butterfly of Sri Lanka.
Nannophrys ceylonensis, commonly known as the Sri Lanka rock frog or the Ceylon streamlined frog, is a species of frog. It used to be placed in the large frog family Ranidae but a phylogenetic study was undertaken using DNA sequences and it is now included in the family Dicroglossidae. It is endemic to Sri Lanka where its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, rivers and streams.
The Bedford-Russell's tree-nymph or Sulawesi tree-nymph is a species of nymphalid butterfly in the Danainae subfamily. It is endemic to Sulawesi, Indonesia.
Sri Lanka is home to 245 species of butterflies with 23 of these being endemic to the island. Of the 245 species, 76, are listed as threatened nationally, while the Ceylon rose is designated as critically endangered.