Science : A new dragon-fly found by scientists

2009-08-07
 

If one sees some odd-looking guys rushing with butterfly-nets through hills, forests and around lakes during spring-summer period, one should know that these are researchers from the Laboratory of Entomology of the Institute of Zoology of the ASM led by habilitat doctor in biology Valery Derzhansky, who are „hunting” insects. Every year they discover new species of insects within fauna of the Republic of Moldova, as well as species new for science. Recently entomologists from the Academy of Sciences for the first time have found a species of dragon-fly from the Order Odonata, Family Libellulidae – Leucorrhinia pectoralis (Charpentier, 1825) new for the territory of our country.

The happiness of scientists was enormous: first of all it was a discovery at the regional level, but also they have been impressed by the beauty of found insects – they had graceful body with fine wings, and live in water only during larval stage. A female’s clutch consists of up to 300 eggs, which she lays on the inferior part of water plants; larvae develop during 1-2 years period, depending on species, and the fly into big world becoming a terrestrial insect.

In spite of ability to tolerate extreme conditions populations of Leucorrhinia pectoralis rarely achieve high numbers, being weak competitors or „colonizers”. This dragon-fly could be met in majority of European states – Austria, Belorussia, Belgium, Bulgaria, Bosnia and Herzegovina, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Italy, Latvia, Lithuania, Luxemburg, Holland, Norway, Poland, Romania, Serbia, Slovenia, Sweden, Switzerland, Ukraine, Russia, Turkey, being protected within the framework of Bern Convention from 1979 and corresponding EU directives. This insect is quite rare near the western area’s border, but becomes more numerous spreading out to the East up to Japan.

Leucorrhinia pectoralis prefers fresh oligotrophic waters, either natural or artificial, not too deep, with rich vegetation, having half of the surface free of plants. It could be met and next to big lakes, but in this case populates just some parts of water bodies. Populations from big lakes are more functional than those from the small water bodies, which are affected by the fluctuations of water level or even their drying out.

Dragon-flies play an important role in the environment, being indicators of water quality. At the same time they are predators feeding on other insects including mosquitoes, thus reducing their number. Disappearing of habitats, wet soils, use of pesticides and insecticides caused a dramatic decrease of dragon-flies number. That is why the discovery of a new species Leucorrhinia pectoralis should encourage us to create and to preserve a healthy environment for human beings and all living creatures from the territory of our country.

The triumph of realizations of the Institute of Zoology entomologists is quite impressive: just during 2008 they have found 25 species of insects new for the fauna of the Republic of Moldova, and at the same time there has been described an absolutely new for science species of collembolan Xenylla andrzeji sp. n.

Tatiana Rotaru