The variation of some qualitative and quantitative characteristics of shells of Arianta arbustorum (LINNAEUS 1758) (Stylommatophora: Helicidae, Ariantinae) from Bosnia and Herzegovina

When Arianta arbustorum (LINNAEUS) was first found in Bosnia and Herzegovina (KOTROSAN 2001), the analyzed specimens displayed a normal variation, although the number of examined individuals was small (11 immature and 12 adult individuals). At this time a detailed study was carried out over a statistically relevant sample. More precise morphological (and statistical) data were presented, relating to the variation of specific morphological characteristics of the above mentioned species, gathered from several populations found in areas of Sarajevo and Visoko (Bosnia and Herzegovina). The results are presented in this article. Introduction Arianta arbustorum (LINNAEUS 1758) is a widespread species of land snails, whose shells have highly variable morphological characteristics (shape, color, size BAMINGER 1997). This species also shows a high degree of adaptation to different life conditions such as type of habitat and altitude. Some of its known habitats include deciduous forests, humid meadows, rocks, and gardens with altitudes of up to 2,700 m above sea level (FECHTER & FALKNER 1990, SCHLESCH 11921). The species has shown a variation in morphological characteristics of its shell, and numerous subspecies and varieties have been described. For example, according to a list made for Austria (REISCHÜTZ 1998) the following subspecies are known: Arianta arbustorum arbustorum (LINNAEUS 1758); A. a. styriaca (KOBELT 1876); A. a. alpicola (A. FERUSSAC 1821); A. a. picea (ROSSMÄSSLER 1837). However, it is necessary to emphasize that there are different arguments regarding the status of the subspecies. This problem became especially obvious after certain combined population and morphological studies (BISENBERGER 1993). The individual subspecies were hence determined according to the statistical analysis of the degree of variation of the selected morphological characteristics. 15 ©Erste Vorarlberger Malakologische Gesellschaft, download unter www.zobodat.at