Lestes dryas
Lestes dryas Kirby, 1890
Local names: Emerald spreadwing, Scarce emerald damselfly, Robust spreadwing, Turlough spreadwing, Glänzende Binsenjungfer, Tangpantserjuffer, Leste dryade, Leste des bois
Species Information
Description
This damselfly is metallic green to bronze-green in colour with light blue pruinosity in mature adults. This species is very similar to Lestes sponsa from which it is difficult to distinguish at first sight, though L. dryas is usually more robust, especially females. In females the distinctive characters are two rectangular spots on the first abdominal segment (S1). The shape being a semi-circle in L. sponsa. The ovipositor is large and extends beyond S10 (in L. sponsa the ovipositor does not extend beyond S10). The pronotum is metallic in colour.
Males have part of the second segment (S2) without the blue pruinosity, unlike L. sponsa which has the whole of S2 pruinose. The lower appendages have curved and enlarged tips, while being straight and narrow in L. sponsa. Rarely some females are blue like the males with blue eyes.
Teneral individuals first have a matte green colour which gives the impression of having a thin grey film covering the green. Soon the green parts become more vivid while the yellow parts become more unsaturated.
Separated from L. barbarus and L. virens by the dark underside of the head, dark pterostigma (when mature) and more extensive pruinosity. Chalcolestes parvidens and C. viridis lack pruinosity, have whitish appendages, a larger and paler pterostigma and a diagnostic thorax marking. L. macrostigma has a larger pterostigma and a darker more pruinose body with almost no hint of green.
Size
Habitat
Lestes dryas is found at standing waters such as ponds, small lakes, bogs and occasionally gravel pits, and is mostly found in habitats with a dense growth of rushes and sedges. It favours standing waters and swamps that partially or completely dry out in the course of summer, but is also found at permanent waters that have shallow edges with rushes or grasses providing warm micro-habitat for the larvae.
Distribution
Lestes dryas is a Holarctic species occuring in both the northern part of Eurasia and North America. In Africa it is found only in the north of Morocco. It is widespread in most of Europe although it is absent from the northern parts of Fennoscandia and has a more scattered occurrence in the Mediterranean region. It is absent from most of the Mediterranean islands. It is common in the lowlands of central Europe but large populations in the south of its range are mostly found in higher altitudes.
Flight Period
April to September
Behavior
Not a species to make any spectacular show and can be easily overlooked. Often it occurs in lesser numbers than similar species and numbers fluctuate a lot between years. However, it can locally be abundant. It usually emerges slightly earlier than the other Lestes species. To find it you might need to find areas where water is hardly seen between the vegetation, like in high grass or between tufts.
Conservation Status
Similar Species
Lestes sponsa
External Links
Genus: Lestes
Lestes, or Spreadwings or Emerald Damselflies, is a genus of damselflies in the family Lestidae. The family hold their wings at about 45 degrees to the body when resting. This distinguishes them from most other species of damselflies which hold the wings along, and parallel to, the body when at rest.
Identification
Lestes damselflies are mostly metallic green and have partly pruinose bodies, large pterostigma and perch with wings spread, hence the name Spreadwings. Teneral individuals may perch with wings folded, and damselflies of other families may occasionally spread their wings, especially when agitated.
The venation has many pentagonal rathern than rectangular cells. The pterostigma and male appendages recall those of Sympecma. However these have a pale brown body, marked with dark bronze, and they parch with closed wings (sometimes folded along only one side of the abdomen)
Calopteryx also have metallic bodies and Epallage even combines pruinosity, long pterostigma and open wings at rest. Both these have multiple cross-veins between the wing base and the node.
Smaller damselflies, such as Erythromma, Ceriagrion and especially Nehalennia, can sometimes have metallic bodies, but they have large lozenge-shaped pterostigma. Their venation is more squarely mesh-like and they have differently configured markings.
In case of doubt, lestids never has longitudinal veins branch off the vein connecting the arculus and subnode.
Behaviour
Lestes males are very active, often hooking up with females of other species or other males but hybrids are not known from Lestes (only from the closely related Chalcolestes parvidens and Chalcolestes viridis.). The male and female oviposit in tandem, and eggs are typically placed in living plant tissue, often well above or away from water.
Lestes are hardy species, their eggs are cold- and drought-resistant, their larvae are fast-growing and the adults are highly mobile. This allows survival in seasonally dry habitats. These features are most strongly developed in L. barbarus. L. viridis might be the least hardy, instead it has specialised in ovipositing into the bark of living twigs.
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.