Arthroplea congener
| Arthroplea congener | ||||||||||
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| Scientific name | ||||||||||
| Arthroplea congener | ||||||||||
| Bengtsson , 1909 |
Arthroplea congener is a mayfly species. It is the only representative of its genus in Europe and one of only two species of the family worldwide.
features
The adults of the species are small (approx. 10 mm long) and predominantly dark brown in color with clear wings without drawing. The male's gonopods are five-limbed. The two tail threads are about twice as long as the body, a terminal filum is missing. In terms of wing veins and general appearance, the animals resemble members of the Ecdyonuridae family .
The larvae have, as a peculiar special formation, strongly elongated and hairy maxillary palps , which surround the head in a semicircle, these are about twice as long as the head width. In living animals, they generate a flow of water through rapid movement and serve as a filter device for filtering out food particles, mainly algae. The small larvae are quite dark in color, the body is highly arched, but the head is flattened. There are seven pairs of triangular to heart-shaped gill leaves on the abdomen. The three tail threads are about the same length.
Ecology and way of life
Arthroplea congener is a kind of standing, at most very slowly flowing water. The inhabited waters are always cool, more or less acidic, mostly quite shallow. Often it is bog waters. The diet as an active filter feeder that creates a current of water itself is unique among European mayfly larvae. It is to be interpreted as an adaptation to life in stagnant waters.
distribution
The species is boreal and more common in Europe, especially in Scandinavia, where it was discovered and described (Sweden). In Central Europe it is extremely rare and limited to the cool, boggy waters of the low mountain ranges. Much evidence is found in spring and stream impoundments (with particularly cool water temperatures). There are finds from the Harz Mountains , the Thuringian Forest , the Bavarian Forest and Upper Lusatia . Other finds follow in the Czech Republic and Slovakia. There are isolated finds from the northeast European lowlands (Poland, Brandenburg). The species is extinct in England. Overall, it is one of the rarest European species with very little evidence. According to the Red List for the Federal Republic of Germany, it is threatened with extinction ( Red List Category 1).
literature
- V. Balthasar (1937): Arthropleidae, a new family of the ephemeroptera. Zoologischer Anzeiger 120 (9/10): 204-230.
- W. Zimmermann (2009): The mayfly Arthroplea congener - an insect of the tundra with a peculiar way of life and extraordinary distribution. Landscape conservation and nature conservation in Thuringia 46 (2): 73–80.