The role of barriers and gradients in differentiation processes of pyrgulinid microgastropods of Lake Ohrid

摘要: Ancient Lake Ohrid is characterized by vertical (bathymetrical) zones within the lake, presumably promoting allopatric speciation due to barriers or parapatric along gradients. Examples lake include belt of Chara algae as well shell zone, both impeding migrations benthic invertebrates. Three potential cases differentiation leading distinct depth forms have been reported for gastropod subfamily Pyrgulinae (Caenogastropoda: Hydrobiidae): Ginaia munda ssp., Macedopyrgula spp. and Ochridopyrgula macedonica ssp. Based on DNA data COI gene from a total 145 specimens, this article aims at investigating these thus patterns in Ohrid. An initial morphometric analysis showed clear correlation shape collecting This morphological trend largely reflected genetic structure respective taxa. The presented here indicate existence strong gradients abiotic biotic factors rather than barriers. Therefore, may be predominant form invertebrates lake. Incomplete lineage sorting, hybridization phenotypic plasticity possibly caused epigenetic mechanisms are discussed possible reasons incongruence between geno- phenotype observed few specimens For third taxon, analyses revealed only weak support previously proposed forms. However, horizontal spring populations was instead, differentiations taxon.