Dynamic gastropods: stable shell polymorphism despite gene flow in the land snail Arianta arbustorum.

HAASE, M.; MISOF, B.

Based on a sequence fragment of mtDNA we analysed the genetic differentiation of the land snail Arianta arbustorum in the Alpine massif Gesäuse, where four morphotypes occur in close vicinity. We aimed at understanding actual and historical evolutionary processes among the morphotypes. With 135 haplotypes diverging up to 12.5%, genetic diversity was extremely high. Phylogenetic analyses indicated that A. arbustorum has colonized the Gesäuse several times in consecutive waves and that introgression of neutral markers across morphotypes and selection on shell shape have played an important role. Gene flow was more likely between locally close, different morphotypes than among distant populations of the same morphotype again indicating that cohesion of morphotypes was mainly due to selection. The actual distribution of morphotypes and haplotypes as well as the high genetic diversity also suggested that the area provided refugia during the Pleistocene glaciations.

GENETIC polymorphisms; POLYMORPHISM (Zoology); SNAILS; GENES; DNA

Journal of Zoological Systematics & Evolutionary Research, 2009, Vol 47, Issue 2, p105

0947-5745

Academic Journal

10.1111/j.1439-0469.2008.00488.x