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FADE NB the vertical lines accompanying each account show the max/min length measured from the front of the head to the tip of the abdomen . Dragonflies and Damselflies The number of dragonflies occurring on the islands is relatively small, thanks to the islands’oceanic isolation and the limited areas of suitable freshwater wetlands . Five dragonflies and one damselfly occur regularly on Madeira and Porto Santo, and 10 dragonflies and two damselflies occur regularly on the Canaries, while a further two migratory dragonfly species have arrived in recent years and could establish permanent populations . All are rather widespread species, except Island Darter, which is endemic to Madeira,Tenerife, Gran Canaria and La Gomera .The smallerWestern Canaries and drier Eastern Canaries hold fewer species, with just four regularly occurring species on Lanzarote and seven species, plus one recent arrival, on Fuerteventura .This compares with 11 species on Tenerife, 10 plus one recent arrival on Gran Canaria, eight on La Gomera, six on La Palma and three on El Hierro . Most species can fly throughout the year in the temperate climate of the islands, but the largest numbers are seen in spring, and a few species, such as Ringed Cascader, do not fly in winter . Many of the African species are highly migratory, and strong S winds can bring influxes of them to the islands, where they can then breed if conditions are suitable . Globe Skimmer has recently reached Gran Canaria in this way, while Long Skimmer has recently reached Fuerteventura; it remains to be seen whether they will establish permanent populations on these islands .There is also a record of a Barbary Featherleg damselfly fromTenerife in March 1971, which is otherwise endemic to North Africa . It is always worth photographing unusual specimens you come across, particularly after S dust-laden storms from North Africa . 3 Ringed Cascader L 53–58mm This boldly marked midsize dragonfly occurs only on Tenerife, La Gomera and Gran Canaria. It is a widespread species in Africa, S Europe, the Middle East and S Asia. However, it prefers fast-flowing sections of permanent streams and rivers, especially rapids, so its habitat is limited on the islands and made more so by the damming of streams at their sources for drinking water and irrigation. It is generally rather local near streams on the islands, but odd individuals will also appear at dams, temporary pools and sheltered beats away from water. Ringed Cascaders fly mostly in the spring and summer months, from March to August. They have long thin bodies and long wings. Adults of both sexes are largely black, with yellow patches down the sides of the abdomen and thin yellow lines down the centre of the abdomen; the female 3♀ shows more distinct black and yellow stripes on the thorax. 183 3♂ 3♀ 3 Small Bluetail L 26–32mm This species occurs only on Madeira and Porto Santo but has a widespread range in Europe, North Africa, Turkey and Russia. It is locally common at suitable sites on both islands, although it tends to have a low weak flight so is easily overlooked. The species quickly colonises temporary pools and flooded areas but also has residual populations in permanent ditches and ponds. Adults have a black abdomen bearing a bold blue spot near the tip, on the last two segments of the body. Immature females 3i are bright orange but become greenish brown as they mature. Small Bluetail is very similar to the two species of bluetails on the Canaries but is thought to be the only damselfly to occur on Madeira currently – although another unknown bluetail species has been caught in the past and may yet still occur. 1 Tropical Bluetail L 28–30mm A widespread and abundant damselfly, Tropical Bluetail occurs from Africa to Japan and New Guinea and is tolerant of polluted and brackish water including stagnant pools. However, in our area the current known range is restricted to tiny colonies in reservoirs at Las Galletas on Tenerife and near Los Llanos de Ariadne on La Palma. The male 1♂ has a bright blue tip to the abdomen and bright green sides to the thorax and eyes, like Sahara Bluetail (see that species for ID tips). The female 1♀ Tropical Bluetail has only two colour forms on the islands, neither of which is shown by Sahara Bluetail: one has an orangey-brown thorax and a uniformly metallic grey-green abdomen and the other a uniformly blackish abdomen, and neither shows a paler blue or...

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