Forest Dormouse, Dryomys nitedula, populations in southern Italy (Calabria region) belong to a deeply divergent evolutionary lineage Bisconti R.1, Aloise G.2, Siclari A.3, Fava V. 3, Provenzano M. 3, Chiocchio A. 1, Nascetti G. 1, Canestrelli D. 1 1Department of Ecological and Biological Science, Universita` degli Studi della Tuscia, ViterBo, Italy 2Museo di Storia Naturale ed Orto Botanico, Università della CalaBria. Via P. Bucci s.n.c., I - 87036 Rende, Italy 3Parco Nazionale dell’Aspromonte, Via Aurora, 1 - 89057 - GamBarie Di S.Stefano In Aspromonte, Italy Dryomys nitedula aspromontis Introduction Within the Italian peninsula, the Forest Dormouse (Dryomys nitedula) populations are restricted to forested mountain areas of two largely disconnected regions: eastern Alps and southern Italy (Aspromonte, Sila, and Pollino mountain massifs). The two populations have so far been descriBed as distinct suBspecies (D. n. intermedius and D. n. aspromontis, respectively) Based on morphological characters1, but a thorough evaluation of their genetic divergence is still lacking. Here, we investigate the pattern of genetic differentiation between D. n. aspromontis and its geographically closest relative D. n. intermedius, in order to fill this gap of knowledge and to promote informed conservation efforts for the Forest Photo credit: A. Pellegrino Dormouse populations in the CalaBria Region. Methods A total of 15 samples of D. nitedula were analysed, 8 from southern Italy (D. n. aspromontis) and 7 from the north-eastern Alps. Patterns of genetic diversity were analysed at the level of sequence variation of one mitochondrial (CYTB) and three nuclear gene fragments (GHR; IRBP; RAG1). Phylogenetic analyses were carried out using Bayesian inference A) Geographic location of the Dryomys nitedula aspromontis samples studied. methods. B) Geographic distriBution of Dryomys nitedula in Europe and neighBouring regions. C) Geographic location of the Dryomys nitedula intermedius samples studied. Results and Discussion D. n. aspromontis and D. n. intermedius were found to be reciprocally monophyletic (no shared haplotypes were found), with all the genetic markers analysed. Genetic divergence between D. n. aspromontis and D. n. intermedius estimated at the mitochondrial CYTB gene was conspicuous (HKY: 0.044) when compared to values previously oBserved among many sister species of rodents. The reciprocal monophyly, deep genetic divergence, and morphological differences, among D. n. aspromontis and D. n. intermedius clearly indicate that D. n. aspromontis belong to a distinct evolutionary significant unit (ESU2), whose taxonomic rank might need re-evaluation3. Furthermore, this ESU is geographically restricted, and strongly fragmented into separate populations inhaBiting distinct mountain massifs (Aspromonte, Sila, Pollino), thus warranting conservation concern. D-G) Phylogenetic trees inferred for the four gene fragments analysed Based on a Further studies are in progress to go deeper inside the Bayesian inference procedure; numBers indicate Bayesian posterior proBaBilities. population’s genetic structure, to investigate its demographic structure, and to identify appropriate conservation efforts for this endemic lineage. References Acknowledgements 1 Von Lehaman, 1964 - Freunde Berlin (n.F.), 4: 31-47. We are grateful to Luca Lapini and A. (Sasà) 2 Moritz, 1994 - Trends Ecol. Evol. 9:373–375. Pellegrino for kindly sharing photos. This 3 Bisconti et al., 2017 - doi: https://doi.org/10.1101/210070 research was supported by grants from the Italian Ministry of Education, University and Research (PRIN project 2012FRHYRA), and from the Aspromonte National Park..