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AimIdentification of potential glacial refugia and post-glacial colonization processes of a flightless, cold-adapted ground beetleLocationCentral and eastern Europe.MethodsWe analysed the genetic structure of 33 Carabus sylvestris populations sampled across its entire distribution range using nuclear and mitochondrial markers. We further compiled occurrence records to develop species distribution models to predict distribution ranges for the last glacial period and the present based on the species’ current climatic niche.ResultsDistinct genetic lineages were detected for a number of mountain ranges and were congruent for both molecular marker systems. Most genetic splits were the results of vicariance, whereas dispersal was rare. Our models suggest that the species’ distribution range was larger and more interconnected in the past.Main conclusionsOur data support multiple glacial refugia for C. sylvestris, some of which were located north of the Alps. Some lower mountain ranges were likely recolonized post-glacially.

Tropical rainforests are well known for their extraordinarily high levels of biodiversity. The origin of this species richness is still debated. For instance, the museum hypothesis states that over evolutionary time more and more species will accumulate with relatively few extinctions. In contrast, the Pleistocene diver- sification model argues that during the last 2 million years, climatic factors (glaciations) caused environ- mental changes that drove isolation and vicariant speciation events. In this study, we construct a molecular phylogeny of the Sundaland (Malay Peninsula, Sumata, Borneo, Palawan) and Greater Minda- nao (Mindanao, Samar, Leyte) tree squirrels (genus Sundasciurus). Our results show that most speciation events in this forest dependent taxon occurred before the Pleistocene and that even the timing of intra- specific splits among populations from different landmasses are relatively old. Additionally, we found unexpectedly high divergence within and between highland populations of S. tenuis on Sumatra and the Malay Peninsula, highlighting the importance of Pliocene events in both speciation and within species divergences in this region