European flat leech
| European flat leech | ||||||||||||
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European flat leech ( Helobdella europaea ) with young animals |
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| Scientific name | ||||||||||||
| Helobdella europaea | ||||||||||||
| Kutschera , 1987 |
The European flat leech ( Helobdella europaea ) is an invasive freshwater species of the order of the proboscis fluke (Rhynchobdelliformes). It was discovered in 1981 and first described in 1985 by the evolutionary biologist Ulrich Kutschera . The flat leeches could be detected in flowing and standing waters in Germany, Australia, New Zealand, South Africa, Hawaii, California and Taiwan and probably come from South America (place of origin unknown).
Occurrence and discovery
In 1980, in Schobbach near Freiburg im Breisgau, a small population of 10 to 18 mm long flat leeches with light pigment spots on the back was discovered. These trunk leeches, identified by two eyes, were not identical to the type species Helobdella stagnalis Linnaeus , 1758, which is common in Central Europe . In contrast to this two-eyed flat leech, which has a gray body color (without papillae) and larger spots, the "Schobbach leeches" are characterized by conspicuous pigmentation patterns. After consultation with the evolutionary biologist Günther Osche and the British leech specialist Roy T. Sawyer, the species was identified as a new species, Helobdella striata Kutschera , 1985, after adult animals were repeatedly found in the wild during 1982, 1983 and 1984 described.
Systematic position
After the southern German flat leech species was given the name " striata ", the first describer was made aware that a South American subspecies ( Helobdella triserialis subsp. Striata ) existed (the original description was published in Portuguese in 1943 and was the Author not known at the time). As a result, the original name had to be changed, so that the South German flat leech was given the final, valid species name Helobdella europaea Kutschera , 1987. As early as the early 1980s, Helobdella europaea individuals were found in aquarium stores in Berlin (but not correctly identified), so that it is very likely that this leech was caused by planting aquarium plants in the Schobbach near Freiburg i. Br. Has arrived. There, small but stable populations have remained outdoors for a number of years. Today it is known that H. europaea is an invasive species that maintains a brood and is believed to be found over many continents via aquarium plants and water snails from South America. A later described species from Australia, Helobdella papillornata Govedich & Davies , 1998, could be recognized as a synonym of the species H. europaea Kutschera , 1987 (i.e., H. papillornata and H. europaea are identical taxa). The exact place of origin of H. europaea is unknown, but could be narrowed down to South America. It is highly probable that the species is identical to Helobdella lineata (Ringuelet), which was originally described as a subspecies from South America in 1943 ; the animals are morphologically indistinguishable. However, this name is preoccupied by another species Helobdella lineata (Verrill, 1874), which was described earlier from North America , so that Kutschera's younger name is the oldest nomenclature description.
Ecology and evolution
The flat gel species discovered in Europe (Freiburg i. Br. Area, southern Germany) feeds by sucking out small host organisms ( oligochaetes , e.g. Tubifex worms; mosquito larvae , e.g. Chironomus ; water snails, etc.) and maintains brood ; both typical for all Helobdella species. The mother animal carries the egg cocoons, larvae and young animals attached to the belly and protects them. The young animals are fed with captured prey (e.g. Tubifex, Chironomus) for about three weeks until they leave the adult leech and thus grow from about 1 to 6 mm in body length (about 1/3 the size of the feeder Mother-tiers). This complex brood care significantly increases the chances of survival of the young, who after leaving the mother leech go to prey independently.
Molecular phylogenetic studies have shown that H. europaea belongs to the Helobdella triserialis species complex found in South America . Although the original habitat and the exact place of origin are unknown, it must be assumed that it is an introduced species from South America. a. occurs in aquariums in Europe and repeatedly finds its way into the field, e.g. B. by disposing of excess plant material from aquariums in streams and ponds. The wide range of prey and the highly developed brood care allow the European flat leech, as an invasive species, to invade new habitats by spreading this species.
Individual evidence
- ↑ a b Ulrich Kutschera: Description of a new species of leech, Helobdella striata nov. sp. (Hirudinea: Glossiphoniidae) Zool. Jb. Syst. (1985) 112, 469-476.
- ↑ Ulrich Kutschera: Notes on the taxonomy and biology of leeches of the genus Helobdella Blanchard 1896 (Hirudinea: Glossiphoniidae) Zool. Number (1987) 219, 321-323.
- ↑ a b c Ulrich Kutschera: The freshwater leech Helobdella europaea (Hirudinea: Glossiphoniidae): an invasive species from South America? Lauterbornia (2004) 52: 153-162.
- ↑ a b c Ulrich Kutschera, Peter Wirtz: The evolution of parental care in freshwater leeches. Theory Biosci. (2001) 120: 115-137.
- ↑ a b c d Mark E. Siddal, Rebecca B. Budinoff: DNA-barcoding evidence for widespread introductions of a leech from the South America Helobdella triserialis complex. Conservation Genetics (2005) 6: 467-472.
- ↑ a b Helobdella europaea: Archived copy ( memento of the original from March 25, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
