Anguis fragilis Linneaus, Grass Snake 1758

• Main Author: Elmberg, Johan
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2023
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Reptilia; Squamata; Anguidae; Anguis; Anguis fragilis; North Sweden
• Online Access: https://doi.org/10.5281/zenodo.8030430; http://treatment.plazi.org/id/03BE87CBFF9F4A70B8887DB346B0FA8F

Slow Worm Anguis fragilis Linneaus 1758 Distribution (Figure 8). Included records from Artportalen (N=360): as there are not any confusion species all reports have been included. Common and widespread in the Southern Boreal and the coastal southern part of the Middle Boreal. From Medelpad and northwards all records have been made within 60 km of the Baltic coast. The vast majority of records is from coastal areas or low altitudes in river valleys. Nevertheless, there are several records from above 300 m altitude in Hälsingland and Ångermanland, and a photo-documented occurrence at 425 m in Medelpad (15 km SW of Stöde). Although most common near the coast, the total lack of records from offshore islands in North Sweden indicates poor dispersal capacity over brackish water. There are no indications of changes in distribution during the last 50 years. Note, though, that the northernmost occurrence presented in the map (Figure 8; lower Byske River valley and the adjacent Tåme area to the north (Västerbotten)) became publicly known as late as 1989, despite the species having been known locally since at least the 1920’s (Södermark 1989). This occurrence has long been regarded as a disjunct population (Elmberg 1995) and perhaps the result of anthropogenic spread, but recent records around Skellefteå have gradually closed the previously supposed 70+ km distribution gap. Habitat and movements . In North Sweden this is the only reptile regularly encountered in closed forest, particularly in mesic stands with scattered deciduous trees and protective undergrowth. However, the most widely used habitats are fairly open, yet with denser undergrowth than those preferred by Vipera berus and Zootoca vivipara : forest edges, natural grasslands, shores, and rock outcrops. Most sightings of Anguis fragilis are made in anthropogenic habitats such as clear-cuts, fields, meadows, roadsides, and near recreational buildings (Figures 13, 19). Although it is the only reptile in North Sweden frequently seen active in cloudy weather, its ...