Marsh Bluet
Enallagma Ebrium, males
Enallagma Ebrium is a Kleinlibellenart from the family of dragonflies Slim ( Coenagrionidae ), which is widely used in Canada and in the north of North America and can be very common in the northern latitudes. The habitat forming lakes and ponds of all sizes, often located in forest areas and typically surrounded by dense vegetation waters. Enallagma Ebrium is a typical representative of the species-rich group of blue-stained goblet Virgin. It is similar to the other members of the genus confusingly, especially of her in the ecological demands almost the same end Enallagma hageni. The first description of the species in 1861 by Hermann August Hagen.
- 5.1 Literature
- 5.2 Notes and references
Features
Enallagma Ebrium is a typical Slim dragonfly with a body length of 28-34 mm and a length of hind wing 16 to 21 millimeters and therefore belongs in the group of blue-stained goblet Virgin one of the smaller representatives. The males have a bright blue color with teardrop-shaped and also blue Postokularflecken on the body- facing side of the compound eyes. They are aligned with the top of another and connected together by a line. The eyes are dark upper side, so that they act as covered by a cap. On the upper side of the thorax, a broad black middle stripe is on both sides with slightly narrower, bright Antehumeralstreifen. The following dark Humeralstreifen are of similar width. In the underlying light blue thorax sides, two short black stripes, the upper is, as for the cup Virgin are typical, only very rudimentary or no training, so that the side surfaces act as no drawing. The elongated abdomen is provided with a slender dragonflies typical drawing. At the lower end of the second segment is a black dot that blends in most instances with the subsequent caudal ring. Also on the other segments three to five are narrow black rings that expand and grow dorsally to the posterior segments of width. The sixth segment is the upper hand for the most part and the seventh predominantly black. The eighth and ninth abdominal segment are without drawing and so blue, the tenth oberseits all black. Rarely, specimens with more extensive black markings of the middle abdominal segments.
The abdomen of the female is stronger built than the males and the upper side completely covered with a black torpedo-shaped drawing, so that the abdominal segments only at the front edge of the segments show three to eight a bright ring. Before the ovipositor on the eighth abdominal segment there is a protruding spine. The thoracic figure corresponds to the males. How not uncommon in the subfamily Ischnurinae, the females come in various colors. There is a androchrome, as the males colored blue shape, and the pale brown or greenish colored either heterochromous forms. The eyes of the females are divided horizontally in color, the lower part is brownish or greenish, the upper brown. On the lower the bright part is usually a dark horizontal band still draws from.
Similar Species
A relatively young evolutionary splitting has led in North America to a large number of partially very similar and difficult distinguishable species. However, the cup Virgin companies are often formed only of a kind, and once determined, it can be assumed that all copies of this population only belong to this type. Preferences for various, at first glance very similar appearing habitat types they seem to separate, although these mechanisms are not yet fully understood.
Males of Enallagma Ebrium are barely distinguishable from those of hageni Enallagma, a differentiation can be made only on the basis of the male abdomen attachments, the details of which may not be perceived when viewed up close. In E. hageni in Lateralsicht is only a single horizontal mandrel while seeing the cerci of E. Ebrium into two equal length, forks about excesses.
Even the females are virtually identical to the females of E. hageni and can be distinguished only on the basis of the shape of the prothorax and the typical shape of the trailing edge. In E. hageni this is bulged in large parts up and significantly above the thorax, while the areas are Ebrium flat at E..
Also very difficult of Enallagma Ebrium how to distinguish E. hageni that are very similar males of Enallagma are annexum, Enallagma boreale, Enallagma civile, Enallagma and vernal. However, these are much larger and up to E. civile merges these, at least in the region of overlap with the adjacent ring not the spread with E. Ebrium, the mushroom-shaped drawing of the second abdominal segment. More commonly occurring blue Slim Dragonflies are characterized by larger shares of black on the middle abdominal segments. The females of E. Ebrium can be confused with the females of Enallagma anna, Enallagma carunculatum, Enallagma civile and Coenagrion resolutum that hold a likewise completely black Abdomenoberseite.
Dissemination
Enallagma Ebrium is far from western Canada to Idaho and Wyoming and west of the Rocky Mountains to Newfoundland, and south spread to Tennessee and West Virginia.
Odonatologische records of Francis White House in 1918 for Alberta, where actually not difficult aufzufindende species such as Enallagma carunculatum, Enallagma clausum and Enallagma hageni and, indeed, Enallagma Ebrium missing, suggest that these expanded its territory in recent decades significantly to the north must have.
The IUCN classifies Enallagma Ebrium one as " not at risk " ( least concern ).
Way of life
Enallagma Ebrium can be very common in the northern latitudes. The habitat forming lakes and ponds of all sizes, often located in forest areas and typically surrounded by dense vegetation waters. In contrast to similar Enallagma hageni bog pools or other acidic waters are usually shunned.
The males rest, some in very large numbers on stems of riparian vegetation or algal mats near the water. Unusually for cups Virgin they remain in the cover of vegetation and steer clear of the open water. The first couple in the wheel reach the reproductive waters around noon, the eggs are laid, alone or with a coupled males in flooding or submerged aquatic plants. It can reach a depth of more than 30 centimeters, the female, and in individual cases without surfacing spend up to five hours under water. The wintering of larvae occurs in the last larval stages.
The flight time of the Imagines differs with the distribution. In the northwest part of its range in the Yukon Territory begins in June and ends in July in British Columbia, it begins in May and extends into August, as well as in Alberta and Montana, but where it also begins in June. In southern Nebraska copies can be encountered until September. In Ontario, Quebec and Wisconsin E. hageni slips in May, in Nova Scotia, Iowa and Maine in June and flies into September, in Ohio even into October.
Naming
The specific epithet Ebrium (Latin ) means " intoxicated ". Since Hermann August Hagen, who described the way in 1861, could have observed this not alive, as he had hitherto never been on the American continent, one can only speculate why he chose this name.