Sympecma paedisca
Sympecma paedisca Burmeister, 1839
Local names: Siberian winter damselfly, Sibirische Winterlibelle, Noordse winterjuffer, Leste enfant, Sibirisk vinterflickalända
Species Information
Description
This species is light brown with portions of the head, thorax and abdomen darker and with a metallic shine. In Europe it can only be confused with Sympecma fusca from which it differs by the pattern on the thorax. On S. fusca the upper dark band's outer edge on the thorax is straight, whereas on S. paedisca it has a bulge. The lower dark band of the thorax is narrower on S. paedisca than on S. fusca and at times not continuous. The two species of this genus are also different in the shape of the male abdominal appendages. The lower appendages are slim, and their tips reach as far as or longer than the tips of the basal teeth of the upper appendages. In spring the eyes turn blue on the males.
Characteristic of this genus is the position of the wings at rest: often kept close to one side of the abdomen. Pterostigma are long and brown, and occupying a different position on the wings; closer to the tip on the fore wing, farther from the tip on the hind wing.
Size
Habitat
Considering its scarcity, S. paedisca is found in a remarkably wide variety of habitats. In Europe, it occurs in mesotrophic to hypertrophic standing or, seldom, slow-flowing waters. These range from large lakes, fenlands and peat-bogs to gravel pits. In the Netherlands it is restricted to mesotrophic fenlands but in north-eastern Germany and Poland it is mainly found in small forest lakes which are often eutrophic or hypertrophic. The species behaves more like a generalist to the east and in eastern Poland it is found in all kinds of standing waters. The habitats always have an abundance of bank side and aquatic vegetation.
As in S. fusca the adults hibernate and mate and lay eggs in spring. Emergence of the new generation takes place in the second half of the summer, after which the adults leave the reproduction site to hibernate often far from their larval habitat. Different habitat types can be suitable for overwintering as long as there is knee-high herbs or grasses protected by higher bushes or trees. This low vegetation is used in autumn for foraging perches and in winter as a refuge, with the surrounding higher vegetation providing shelter from the wind. In the Netherlands it was noted that the adults prefer relatively dry conditions during winter, suggesting that they are sensitive to moisture.
Distribution
Sympecma paedisca is rare to uncommon in most of its European range with the exception of the north-east. The latter area include large parts of Poland, the Baltic states and the southern margin of Finland. The species is probably under-recorded in Belarus, northern Ukraine and European Russia. In western Europe, it is limited to a narrow strip running from the Netherlands across northern Germany to Poland. In central Europe it occurs on the northern side of the Alps, in Bavaria, Baden Württemberg and Austria, with additional relict populations found in the south-west of Switzerland and in the western mountains of the Czech Republic. South of the Alps, the species survives in northern Italy but is extinct in lower alpine area of south-eastern France.
Flight Period
August-September first year and then April-May the next year.
Behavior
Belonging to the only genus to hibernate as imagos, Sympecma paedisca leaves water at the end of the summer to sit on a grass straw and wait for the spring. It seems these overwintering areas must not be too humid. In the spring it is one of the first to return to the water again.
Conservation Status
Similar Species
Sympecma fusca
External Links
Genus: Sympecma
Sympecma is a genus of damselfly in the family Lestidae. Also called Winter damsels they are the only genus in Europe to overwinter as hibernating adults.
Identification
Sympecma have brown bodies with dark bronze dorsal markings. The pale brown pterostigma is and elongated rectangle, covering two hind cells. The pterostigma on the front wing is distinclty placed further from the body than on the hind wing. This can easily be seen on resting individuals, where the pterostigma hardly overlap.
Separation from other genera
The wing venation recall Lestes, with many pentagonal rather than rectangular cells. Also long pterostigma and male appendages recall Lestes. However, the individuals never show the bright green colouration of Lestes (even if young individuals can have brown-greenish metallic markings). The wings of Sympecma are narrower and more pointed. Lestes often perch with wings half spread, while Sympecma rest with wings closed, often with both wings on one side of the abdomen. On Lestes also the pterostigma of the forewing and hindwing overlap broadly.
The hind edge of the pronotum of Sympecma is trilobed, two incisions produce a conspicuous central lobe with two lateral lobes, whereas in Lestes the edge is uniformly rounded.
The Sympecma female appendages are notably large and pale, while the ovipositor is weak and short, the tip extending only halfway along S10.
Brown females of Enallagma have similar abdominal markings, but their pterostigma are small and lozenge-shaped. They have short dark appendages, a spine at the ovipositor base. Their markings are differently configured and blacker on the head, thorax, and postocular spots.
Behaviour
Sympecma can be hard to find, being brown and their behaviour doesn't help. At rest, the wings are closed and often both are held along one side of the abdomen. Perching individuals often press their body tight against the reed or twig, to be less conspicuous. Adults emerge in late summer and hibernate as adults. They reproduce in the following spring. This is unlike all other European odonates that winter as eggs or larvae. After emergence they dwell in open landscapes, such as rough meadows and heaths with shrubs or forest borders, some distance away from water. Here, they forage during autumn before spending the winter in a more or less motionless state. They perch on an exposed straw or twig, pressed against a stem, or concealed under stones and bark. Few adults are seen from November to March, but on a sunny day they might appear. Males and females oviposit in tandem, most often in floating dead plant material.
Family: Lestidae
The Lestidae are a rather small family of cosmopolitan, large-sized, slender damselflies, known commonly as the spreadwings or spread-winged damselflies.
The two subfamilies in Lestidae are Lestinae and Sympecmatinae. Damselflies in the Lestinae rest with their wings partly open, while those in the Sympecmatinae, the reedlings, ringtails, and winter damselflies, rest with their wings folded. The exact taxonomy of the family is disputed, with some authorities including twelve genera and some eight.
Characteristics
While most damselflies rest with their wings folded together, most members of the family Lestidae hold them at an angle away from their bodies. The pterostigma is noticeably elongated. The quadrilateral has an acute angle at the end. The body has a greenish, metallic shine. The anal appendages of male spreadwings are long and strongly curved.
Breeding takes place in slow-moving or still water in stream backwaters, swamps, marshes and temporary pools. The nymphs have a long abdomen and a distinctive prementum.