Calycopteryx | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Family: | Micropezidae |
Genus: | Calycopteryx Eaton, 1875 |
Species: | C. mosleyi |
Binomial name | |
Calycopteryx mosleyi Eaton, 1875 | |
Calycopteryx is a genus of stilt-legged fly with only a single recognized species, the Calycopteryx mosleyi (sometimes misspelled moseleyi) native to the Kerguelen Islands and Heard Island of the south Indian Ocean, [1] [2] first described by Alfred Edwin Eaton in 1875. [3] It is characterized by its tiny size and flightlessness. [4]
Calycopteryx mosleyi has wings that have shrunk and turned into a fat reserve, probably due to the strong winds of the Kerguelen archipelago that make flight for tiny insects almost impossible. [5] This could indicate that they migrated from elsewhere to the islands they are currently found and evolved there separately from the other species of the family Micropezidae. They are the only recognized species of the genus. [1]
Two subspecies are recognized:
These tiny flies can reach 7 mm in length and have a greenish-brown color. [4] They have very long legs, which are darker than their body. Their abdomen is hairless and matte brown in color. Their larvae are maggots which are white in color. [4]
Calycopteryx mosleyi lives in the Kerguelen Islands and Heard Island which are part of the Southern Indian Ocean Islands tundra ecoregion. The climate is classified as ET (tundra climate) under the Köppen climate classification, which is technically a form of polar climate, as the average temperature in the warmest month is below 10 °C (50 °F). [7] Apart from the cold, the climate is also characterized by extreme windswept, generally low cloud cover and snowfall occurrence through most of the year.
They are closely associated with the Kerguelen cabbage, a plant which the individuals of the C. mosleyi are its main pollinators, and these flies are typically found in large numbers on the leaves of the Kergeulen cabbages across the islands of the Kerguelen archipelago and Heard Island. [4] This cabbage is a main trophic resource for both adult and larvae of the C. mosleyi and many of the flies spent most of their lives on cabbages. [4] [8] Kerguelen cabbages are distributed from littoral margins to further inland and are usually found in non-saline areas. This in combination with the fact that adults of C. mosleyi are found at the axil of the leaves where rainwater is accumulated and salinity is null or low, brought the attention of scientists because it makes the C. mosleyi quite exceptional among the invertebrates of subantarctic region, most of which live in environments with high levels of salinity. [8] However, newer studies reveal that there is a large number of C. mosleyi living in areas devoid of Kerguelen cabbages, like seaweed habitats [8] consisting mostly of kelps of the Macrocystis pyrifera species that were washed ashore. [4] They have also been found in other coastal locations, like penguin colonies, where they have a similar role as in the seaweed ecosystems, they decompose organic matter. [5]
The population of Calycopteryx mosleyi has greatly reduced since the arrival of humans on the islands it inhabits, mostly due to the animals introduced to the ecosystem by them.
Rabbits were brought from South Africa to some of the islands of the Kerguelen archipelago in 1874 and the following years. [9] These little lagomorphs have been feeding on the Kerguelen cabbage ever since, resulting in reduction of its population and obviously a destruction of C. mosleyi's habitat in some areas. [9]
In 1913, beetles of the Merizodus soledadinus species of South America were also introduced to the Kerguelen Islands. They prey on the larvae of C. mosleyi and as a result the population of the indigenous flies has declined greatly since the beetle's introduction to the ecosystem. The Merizodus soledadinus could eventually outnumber the Calycopteryx mosleyi in some of the islands resulting in C. mosleyi's disappearance. [5]
Like most of the fauna of the subantarctic, Calycopteryx mosleyi is also threatened by the climate change, with the rising temperature disrupting the balanced ecosystem. [10]
The Territory of Heard Island and McDonald Islands is an Australian external territory comprising a volcanic group of mostly barren Antarctic islands, about two-thirds of the way from Madagascar to Antarctica. The group's overall land area is 372 km2 (144 sq mi) and it has 101.9 km (63 mi) of coastline. Discovered in the mid-19th century, the islands lie on the Kerguelen Plateau in the Indian Ocean and have been an Australian territory since 1947.
The Kerguelen Islands, also known as the Desolation Islands, are a group of islands in the sub-Antarctic region. They are among the most isolated places on Earth, with the closest territory being the Heard Island and McDonald Islands territory of Australia located at roughly 450 km (240 nmi), and the nearest inhabited territory being Madagascar at more than 3,300 kilometres in distance. The islands, along with Adélie Land, the Crozet Islands, Amsterdam and Saint Paul islands, and France's Scattered Islands in the Indian Ocean, are part of the French Southern and Antarctic Lands and are administered as a separate district.
In physical geography, tundra is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra.
The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar climate has an average temperature of less than 10 °C (50 °F). Regions with a polar climate cover more than 20% of the Earth's area. Most of these regions are far from the equator and near the poles, and in this case, winter days are extremely short and summer days are extremely long. A polar climate consists of cool summers and very cold winters, which results in treeless tundras, glaciers, or a permanent or semi-permanent layer of ice. It is identified with the letter E in the Köppen climate classification.
The Auckland Islands are an archipelago of New Zealand, lying 465 km (289 mi) south of the South Island. The main Auckland Island, occupying 460 km2 (180 sq mi), is surrounded by smaller Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island, and Green Island, with a combined area of 570 km2 (220 sq mi). The islands have no permanent human inhabitants.
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alpine tundra gets lower until it reaches sea level, and alpine tundra merges with polar tundra.
Pringlea antiscorbutica, commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus Pringlea in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen Islands, and its generic name derives from Sir John Pringle, president of the Royal Society at the time of its discovery by Captain James Cook's Surgeon, William Anderson in 1776.
The tree line is the edge of a habitat at which trees are capable of growing and beyond which they are not. It is found at high elevations and high latitudes. Beyond the tree line, trees cannot tolerate the environmental conditions. The tree line is sometimes distinguished from a lower timberline, which is the line below which trees form a forest with a closed canopy.
The Antarctic realm is one of eight terrestrial biogeographic realms. The ecosystem includes Antarctica and several island groups in the southern Atlantic and Indian oceans. The continent of Antarctica is so cold that it has supported only 2 vascular plants for millions of years, and its flora presently consists of around 250 lichens, 100 mosses, 25–30 liverworts, and around 700 terrestrial and aquatic algal species, which live on the areas of exposed rock and soil around the shore of the continent. Antarctica's two flowering plant species, the Antarctic hair grass and Antarctic pearlwort, are found on the northern and western parts of the Antarctic Peninsula. Antarctica is also home to a diversity of animal life, including penguins, seals, and whales.
The Crozet Islands are a sub-Antarctic archipelago of small islands in the southern Indian Ocean. They form one of the five administrative districts of the French Southern and Antarctic Lands.
The rockhopper penguins are three closely related taxa of crested penguins that have been traditionally treated as a single species and are sometimes split into three species.
The subantarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands in the southern parts of the Atlantic, Indian, and Pacific oceans, especially those situated north of the Antarctic Convergence. Subantarctic glaciers are, by definition, located on islands within the subantarctic region. All glaciers located on the continent of Antarctica are by definition considered to be Antarctic glaciers.
The Kerguelen Islands are part of the Southern Indian Ocean Islands tundra ecoregion that includes several subantarctic islands. In this cold climate plant life is mainly limited to grasses, mosses and lichens, although the islands are also known for the indigenous edible Kerguelen cabbage. The islands are at the Antarctic Convergence, where cold water moving up from the Antarctic mixes with the warmer water of the Indian Ocean. As a consequence, marine mammals, especially seals, and seabirds and penguins are numerous.
The Southern Indian Ocean Islands tundra is a tundra ecoregion that includes several subantarctic islands in the southern Indian Ocean.
The northern rockhopper penguin, Moseley's rockhopper penguin, or Moseley's penguin is a penguin species native to the southern Indian and Atlantic Oceans. It is described as distinct from the southern rockhopper penguin.
Poa cookii, sometimes called Cook's tussock-grass or bluegrass, is a species of tussock grass native to various subantarctic islands. The specific epithet honours British explorer James Cook who visited the Kerguelen Islands in 1776.
Île de la Possession, or Possession Island, formerly Île de la Prise de Possession, is part of the Subantarctic Crozet Archipelago. Administratively, it is part of the French Southern and Antarctic Lands. It is an important nesting site for seabirds.
The Îles Nuageuses comprise a group of small islands that are part of the Kerguelen archipelago, a French territory in the southern Indian Ocean. They are an important breeding spot for seabirds, especially penguins and albatrosses, and for fur seals.
Megaherbs are a group of herbaceous wildflowers growing in the New Zealand subantarctic islands and on the other subantarctic islands. They are characterised by their great size, with huge leaves and very large and often unusually coloured flowers, which have evolved as an adaptation to the harsh weather conditions on the islands. They suffer from overgrazing due to introduced mammals.
Embryonopsis halticella is a species of flightless moth found on islands of the sub-Antarctic Indian Ocean.