Wednesday, October 22, 2014

Papilio demoleus

                                                          Papilio demoleus

Papilio demoleus is a scientific name of the common lime butterfly.

Papilio demoleus is a common and widespread swallowtail butterfly. It gets its common names from its host plants, which are usually citrus species such as the cultivated lime. Unlike most swallowtail butterflies, it does not have a prominent tail. The butterfly has also been referred to as the Butterfly of Death,a name it shares with a morphologically similar species, Papilio demodocus, which flies in Africa. The butterfly is a pest and invasive species from the Old World which has spread to the Caribbean and Central America.

                           Life cycle of the butterfly

The female butterfly goes from plant to plant, laying a single egg at a time on top of a leaf which it holds onto with its legs, and flies off as soon as the egg is laid. The egg is round, light yellowish in colour, flattened at the base, smooth-surfaced and about 1.5 mm in height. Fertile eggs develop a small red mark at the apex.

The newly hatched caterpillar stays in the middle of the upperside of the leaf. The first instar of the caterpillar is black, with a black heads and two rows of sub-dorsal fleshy spines. The second, third and fourth instars are dark, with glossy, dark-brown head, and white markings on the 8th and 9th segments of the caterpillar which resemble a white patch of uric acid deposited in a bird's droppings, helping them escape predation while remaining in moderately open places.

As the instars progress, this resemblance is lost. From the fifth instar onwards, the caterpillars now turn cylindrical in shape, taperered towards the rear, and uniformly pale green in colour with a white sub-spiracular band. An additional black band is developed on the 4th and 5th segments with two black and two bluish spots on them. The 8th and 9th segments, which earlier provided the camouflage markings now develop a brown and white band. At this stage, the caterpillars are forced to inhabit secluded places.

The pupa, which is rugose, stout and 30 mm in length, has two projections to the front on its head and also one on its thorax and resembles that of the Common Mormon Papilio polytes, the difference being that the Common Mormon pupa has a deeper cut between the projections and its abdomen is more protruded on the sides, having a small point.

The pupa is dimorphic with regards to colour, with the colour developing according to the prevalent colour and texture in the background. The green morph, which is found amongst green vegetation and smoother textures, is light green and unmarked or with yellow dorsal markings. When situated among brown or dry objects, the pupa tend to turn light grey-brown to pink-brown and develop cryptic dark brown and black striation.

Captive breeding of Papilio demoleus in Riyadh have revealed the following data about the life-span of various stages at that locality:[15]

No of generations per year: Eight.
Duration of egg stage: 3.1 to 6.1 days.
Duration of larva stage: 12.9 and 22.7 days.
Duration of pupa stage: 8.0 to 22.4 days.
Duration of adult stage: 4 to 6 days with average of 5.1 days.



No comments:

Post a Comment