Wednesday, May 20, 2009

United Nations Insects FDC

United Nations FDC
Name: Endangered Species 2009
Date of Issue: 16 April 2009

These are the seventeenth set of stamps in UNPA's multi-year series "Endangered Species". The series was launched on 3 March 1993 to highlight the need for the protection of endangered species throughout the world. This year the series "Endangered Species" feature a variety of insects.

Denominations:
42c:
Emperor Dragonfly (Anax imperator)
The emperor dragonfly is one of the largest European dragonflies, with a length of 8 cm and a wingspan of 11 cm. It is a spectacular sight, with broad wings and powerful flight.

After emerging from their larval stage, both sexes are pale green with brownish markings. The legs are brown, becoming yellowish towards the base; the wings have black veins, and take on a yellowish-brown tinge with age.

Males develop a bright blue abdomen with a black fish-bone line passing down the centre; the thorax and head are green, and the prominent eyes are blue.

Females have similar markings to males, but are mainly green in colour, becoming brownish on the last few segments of the abdomen.

This dragonfly has a broad global distribution; it is found in Europe from Portugal to Germany in the north, and extends eastwards to Central Asia. It is also known in North Africa and the Middle East.

The species breeds in a range of aquatic habitats, including large ponds, canals, slow-flowing rivers, lakes and flooded gravel pits, but in all cases there must be a plentiful supply of marginal vegetation that emerges from the water.

Many dragonflies are vulnerable to water pollution and loss of habitat by infilling of ponds and drainage of water bodies.

42c: Southern Wood Ant (Formica rufa)
The southern wood ant is commonly found throughout southern England in both coniferous and broad leaf broken woodland and parkland. They are the largest native ant species of the Brit ish isles, measuring 8-10 mm in length,
and they all are generally reddish in colour.

Nests of these ants are large, conspicuous, dome-shaped edifices, usually situated in woodland clearings, where the sun's rays can reach them. A single colony can consist of more than 250,000 individual workers, which aggressively defend the territory.

A common diet for a wood ant colony is invertebrates found around the nest, particularly aphids harvested from the surrounding trees, although they are also voracious scavengers.

Studies of the southern wood ant have shown that around 60,000 food items are taken to the nest each day.

Although the reasons for the decline are not fully understood, it is thought that loss of woodland habitat and unsuitable management practices leading to overgrowth of sunny areas, as well as disturbance by humans and livestock, may be involved.

42c: Rosalia Longicorn (Rosalia alpina)
The rosalia longicorn is one of the most striking and elegant of all beetles, with its beautiful steely blue-grey colouration and
large, dominating black spots. The extremely long antennae on the front of the head are also adorned with groups of black hairs, which contrast dramatically with the blue-sky colour of the bare parts, appearing as alternating bands of black and blue. Males can be distinguished from females by their longer antennae, which can greatly exceed the length of the body.

The species is wide-ranging, from Northern Africa, across Europe and the Middle East to the Russian Federation. It lives in deciduous forests where there is a reasonable amount of sunlight exposure. Larvae develop in dead, decaying, relatively dry wood, or on living trees in wounds and abrasions. Although adults are capable of flight, they are often content to simply remain on or near the tree trunks in which they developed as larvae.

The rosalia longicorn is largely threatened by habitat loss and destruction due to changes in methods of forest maintenance and felled wood processing. Trees are being cut down and harvested for timber and firewood before they reach a suitable age to be able to support developing larvae, and dead wood is being rapidly removed to facilitate "reforestation". The rosalia longicorn also suffers from collection from the wild for commercial trade, with its distinctive pattern and bright colour making it attractive to collectors.

42c: Apollo Butterfly (Parnassius apollo)
The Apollo is a beautiful white butterfly, decorated with large black spots on the forewings and red eyespots on the hindwings. These striking red eyespots can vary in size and form depending on where the butterfly comes from. The bright red colour often fades in the sun, causing the eyespots of older individuals to appear more orange. The wings are shiny, with slightly transparent edges.

The Apollo butterfly is found throughout Europe and into Central Asia. It inhabits mountain meadows and pastures, up to 2,000 metres above sea level, where there are plenty of nectarproviding flowers.

The beautiful Apollo butterfly has long been prized by collectors, who aim to possess as many of the variants as possible. Over-collecting is believed to have caused populations to decline in some areas, such as in Spain and Italy, but habitat change is thought to be a far more significant threat to the survival of this species. Climate change and acid rain have also been implicated in its decline.

Laws exist to protect the Apollo butterfly in many countries. It is also listed in CITES Appendix II, which restricts trade in this species.

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