Facts about brambles
In Central Europe the representatives of the subgenus Rubus (bramble) form a complex of a few sexual taxa and innumerable polyploid apomicts. The few sexual and diploid brambles of Europe should be treated as true "biological species". The others form an apogamous complex with special combinations of morphological and ecophysiological features which are more or less stabilized by apomixis. Within this complex there are many biotypes with unmistakable constant characters, both morphologically and ecologically, and with wide distribution (in Central Europe about 350 taxa). They can be recognized by an experienced batologist usually at first glance (if the range of variation due to soil and light conditions is well understood). These biotypes have, apart from the manner by which they produce their progeny,the same behaviour as sexual species: constancy of features and constancy of progeny. They are treated therefore as species and may, if wanted, be regarded as "taxonomic species".
In modern batology an agreement has been established: Only biotypes with a wide distribution (500 km up to more than 1000 km) and regionally distributed biotypes (diameter of distribution area about 50-250 km) should be treated as species. On the other hand unstabilized single biotypes, hybrids of unknown origin or their derivatives with only a local distribution should not be validated as species and do not merit a special taxonomic treatment. Otherwise 10000s of different singular and local biotypes ought to be named and would lead taxonomy ad absurdum. The number of species which one really has to deal with in a certain part of Europe decreases considerably after thorough taxonomic and nomenclatural revision and if only regionally and widely distributed bramble species are taken into consideration.
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