Udaspes folus

Taxobox | name = Grass Demon ("Udaspes folus")


image_width = 240px
image_caption = Grass Demon, Mumbai
regnum = Animalia
phylum = Arthropoda
classis = Insecta
ordo = Lepidoptera
familia = Hesperiidae
subfamilia = Hesperiinae
genus = "Udaspes"
species = "U. folus"
binomial = "Udaspes folus"
binomial_authority = (Cramer, 1775)

The Grass Demon "Udaspes folus" is a small but prominent butterfly found in India that belongs to the Skippers or the Family Hesperiidae family. It is regarded as an occasional pest of Ginger and Turmeric.

Description

The Grass Demon ("Udaspes folus") is a small butterfly with a wingspan of about 4 to 4.8 cm. It is black with a large white spot on the upperside of the hind wing and several smaller whites spots on the forewing. The underside of its wings is mostly white with brown edges and spots.

Range

Sri Lanka, South India to Saurashtra, Maharashtra, Gujarat, Madhya Pradesh, Uttar Pradesh, West Bengal, Himachal Pradesh to North East India and onto Myanmar. China. Thailand. Malayasian Peninsula. Indonesia, Sumbawa. Australia.

tatus

Not Rare in India. Rare or Very Rare in certain parts of its global range. This butterfly is seen chiefly during the monsoon, perhaps due to its larval host plants growing at this time of the year.

Habitat

The Grass Demon is to be found in deciduous and semi-evergreen forests. It prefers the edges of open spaces rather than the deep forest shade or open sunlight. It is most abundant in the more open regions of hilly jungle. It is also encountered on the plains at some distance from such terrain. It occurs up to 8000 feet in the hills of South India and up to 5000 feet in the Himalayas.

Habits

The Grass Demon prefers forest edges or clearings where dappled light is present. Its black and white colouration may have evolved to take advantage of the dappled light in these areas. The pied pattern which seems prominent in the open is effectively disruptive in the shade and the butterfly is difficult to locate once it settles down.

It is a bold insect and not easily disturbed. It usually flies in the shade among bushes and under trees keeping low and close to the ground. From time to time, it takes short flights, and, occasionally, much longer excursions into the open clearings. Its flight is quick and the path is very erratic making it very difficult to track when in flight.

When basking it sits on the upperside of leaves of herbs or bushes with its hind wings pressed flat against the surface and its fore wings held half open at an angle above the hind wings.

This butterfly also has a unique wing flashing display most often seen just after it has alighted on a leaf. It will move its hind wings down toward the leaf surface. When the hind wings are about half way down the fore wings also start moving downwards. On the upward beat both wings are moved simultaneously till the hind wings come together. Then it again begins the downward beat. Each beat is performed very slowly and the butterfly is very conspicuous during this time.

This display is unique since no other peninsular Indian butterfly is known to display the capability of moving forewings and hindwings separately.

The Grass Demon is a nectar lover and has a long proboscis compared to body size. This makes it easy to get to nectar of flowers with long corolla tubes. In gardens, the Common Periwinkle "Vinca rosea", and, the "Lantana" are its favourite flowers. It rarely visits bird or dung droppings. It is fond of water and often seen perched on a stone in a stream-bed.

Lifecycle

The butterflies emerge in February or March and lay eggs before they die. The eggs remain dormant till the rains, that is, usually the month of May, when they hatch. The caterpillars pupate in September-October and the adults emerge four to six months later. In some cases the caterpillars pupate later and in these cases the pupa remain dormant, throughout the dry season, till May when the rains begin.

Eggs

The female normally sits on the underside of the leaf of the host plant and lays a single egg. The egg is reddish and appears smooth and dome shaped. When about to hatch it turns white with a red top.

Larva

Soon after hatching, the caterpillar does not consume the eggshell completely and it makes itself a spacious cell and hides inside it. The caterpillar is sluggish and comes out to feed only at night. Even when disturbed it is reluctant to leave its cell.

The caterpillar is a light uniform leaf green color with a dark green pulsating line on the back and a relatively small, dark head. The full grown larva has the habit of resting with the first three segments contracted, so as to give the appearance of being humped. It always lies closely applied to the leaf, by turning over a riangular piece from the edge onto the upper surface over itself.

Pupa

is long and cylindrical, watery green in colour. It has a long conical projection in front of the head. The eyes are easily seen but do not protrude out of the outline of the pupa. The pupa broadens towards the shoulders and the abdomen gradually tapers to the last segment.

The most striking characteristic of the pupa is its proboscis. It is long and thin generally extending up to and a little beyond the tip of the abdomen. The pupa is the same color of the caterpillar and unmarked. It is covered in a thin layer of white powder. The body band is neither too tight nor too loose and allows the pupa to wriggle if disturbed.

Foodplants

The Grass Demon feeds on ginger, turmeric, and their relatives "Curcuma aromatica", "Curcuma decipiens", "Hedychium" sp. and other plants of Family "Sctiaminae". It has also been recorded on "Zingiber" sp. and on Grasses.

References

* Evans, W.H. (1932) The Identification of Indian Butterflies. (2nd Ed), Bombay Natural History Society, Mumbai, India
* Gaonkar, Harish (1996) Butterflies of the Western Ghats, India (including Sri Lanka) - A Biodiversity Assessment of a threatened mountain system. Journal of the Bombay Natural History Society.
* Gay, Thomas; Kehimkar, Isaac & Punetha, J.C.(1992) Common Butterflies of India. WWF-India and Oxford University Press, Mumbai, India.
* Kunte, Krushnamegh (2005) Butterflies of Peninsular India. Universities Press.
* Wynter-Blyth, M.A. (1957) Butterflies of the Indian Region, Bombay Natural History Society, Mumbai, India.

ee also

*Hesperiidae
*List of Butterflies of India
*List of Butterflies of India (Hesperiidae)