First establishment of microsatellite markers in clausiliid snails (Mollusca: Gastropoda: Clausiliidae).

BACKGROUND: Clausiliidae (door snails) are gastropods with a very high diversity concerning shell morphology, especially of their complex closing apparatus, which provides the most important diagnostic traits for classification of taxa. Due to the high variability, a high number of taxa has been described, though their systematics and taxonomy is partially controversially discussed. Montenegrina is the second most speciose door snail genus in Europe. It is an obligate rock-dwelling land snail and has, compared to its complex systematics, a rather small distribution range in the western parts of the Balkan Peninsula. The different taxa themselves show a very narrow and patchy distribution range. As Montenegrina is comprehensively sampled over the whole distribution range, it is a perfect study system for general questions on speciation and morphological differentiation in land snails. To study the amount of gene flow between geographically close or co-occurring populations, highly polymorphic markers are needed.

RESULTS: Thirteen microsatellite loci with a tetranucleotid repeat were isolated and tested in three geographically close Montenegrina populations (two populations of M. dofleini prespaensis from the Prespa Lake, n = 35 and one population from M. stankovici from the Ohrid Lake, n = 20). The number of alleles per locus ranged from 2 to 27. No significant linkage disequilibria between the same two loci were found in all three tested populations. The deviation from Hardy-Weinberg equilibrium reveal only for two loci a significant deviation from HWE in more than one population (Mont_5483 and Mont_4477).

CONCLUSION: The 13 newly established genetic markers will help to gain better insights to the population genetic structure of Montenegrina and might reveal new results about speciation processes in co-occurring taxa. Furthermore, these microsatellite loci could also be tested in other clausiliid species.