Xerobdellidae
| Xerobdellidae | ||||||||||||
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European country leech ( Xerobdella lecomtei ), young animal |
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| Scientific name | ||||||||||||
| Xerobdellidae | ||||||||||||
| Moore , 1946 |
Xerobdellidae is the name of a family of land-living flukes in the subordination of the jaw rule , which are common in Central America , South America and Europe and feed partly as predators of small animals, partly as parasites on blood that they suck on vertebrates .
features
The flukes of the family Xerobdellidae have three monostichodont (with a row of teeth) jaws in their mouth. As with other jaw rules , there are five pairs of eyes on the head, which are arranged in an "eye arch" similar to the Haemadipsidae , with the fourth and fifth pair being separated by one or two eyeless rings. The externally not visible segments each comprise 8 to 12 outer rings. The leeches have paired nephridia on their ventral side , of which - in contrast to the Haemadipsidae - the 17th pair is missing. Characteristic of the Xerobdellidae is the common (unpaired) medioventral nephridial outlet at the base of the posterior suction cup.
The three genera and their distribution
According to Elizabeth Borda, Alejandro Oceguera Figueroa and Mark E. Siddall, the Xerobdellidae family includes the following genera :
The three species of the genus Xerobdella are common in Europe - Xerobdella lecomtei in the Eastern Alps ( Austria , Slovenia , Bavaria ), Xerobdella anulata in the Dinaric Mountains (Slovenia, Croatia , Bosnia and Herzegovina ) and Xerobdella praealpina in northern Italy between Lake Garda and Austria.
The genus Mesobdella is restricted to Chile , while the species of Diestecostoma are the most widespread and can be found in both Central America and northern South America . Based on this distribution, Borda, Oceguera and Siddall assume that the family is a relic group that goes back to the time of the supercontinent Pangea and could have been formed about 250 million years ago.
Systematics
The American zoologist John Percy Moore founded his own family Xerobdellidae in 1946, which he separated from the externally very similar Haemadipsidae , with the anatomical peculiarities of the nephridia and genital organs. The status of a separate family was confirmed in 2009 by Borda, Oceguera and Siddall in their comparative molecular genetic studies of nuclear DNA and mitochondrial DNA .
literature
- Elizabeth Borda, Alejandro Oceguera-Figueroa, Mark E. Siddall (2008): On the classification, evolution and biogeography of terrestrial haemadipsoid leeches (Hirudinida: Arhynchobdellida: Hirudiniformes). Molecular Phylogenetics and Evolution 46 (1), pp. 142-154.
- James H. Thorp, D. Christopher Rogers: Thorp and Covich's Freshwater Invertebrates: Keys to Nearctic Fauna. Elsevier, Amsterdam 2015. p. 255.
- Uwe Jueg: Xerobdella praealpina Minelli, 1971 (Hirudinea, Xerobdellidae) in Austria and Slovenia. Lauterbornia 79, pp. 145-149.