A de novo genome assembly and annotation of the southern flying squirrel (Glaucomys volans)

Northern (Glaucomys sabrinus) and southern (Glaucomys volans) flying squirrels are widespread species distributed across North America. Northern flying squirrels are common inhabitants of the boreal forest, also occurring in coniferous forest remnants farther south, whereas the southern flying squirrel range is centered in eastern temperate woodlands. These two flying squirrel species exhibit a hybrid zone across a latitudinal gradient in an area of recent secondary contact. Glaucomys hybrid offspring are viable and can successfully backcross with either parental species, however, the fitness implications of such events are currently unknown. Some populations of G. sabrinus are endangered, and thus, interspecific hybridization is a key conservation concern in flying squirrels. To provide a resource for future studies to evaluate hybridization and possible introgression, we sequenced and assembled a de novo long-read genome from a G. volans individual sampled in southern Ontario, Canada, while four short-read genomes (two G. sabrinus and two G. volans, all from Ontario) were resequenced on Illumina platforms. The final genome assembly consisted of approximately 2.40 Gb with a scaffold N50 of 455.26 Kb. benchmarking universal single-copy orthologs reconstructed 3742 (91.2%) complete mammalian genes and genome annotation using RNA-Seq identified the locations of 19,124 protein-coding genes. The four short-read individuals were aligned to our reference genome to investigate the demographic history of the two species. A principal component analysis clearly separated resequenced individuals, while inferring population size history using the pairwise sequentially Markovian coalescent model noted an approximate species split 1 million years ago, and a single, possibly recently introgressed individual.

A de novo genome assembly and annotation of the southern flying squirrel (Glaucomys volans)

Northern (Glaucomys sabrinus) and southern (Glaucomys volans) flying squirrels are widespread species distributed across much of North America. Northern flying squirrels are common inhabitants of the boreal forest, also occurring in coniferous forest remnants farther south, whereas the southern flying squirrel range is centered in eastern temperate woodlands. These two flying squirrel species exhibit a hybrid zone across a latitudinal gradient in an area of recent secondary contact. Glaucomys hybrid offspring are viable and can successfully backcross with either parental species, however, the fitness implications of such events are currently unknown. Some populations of G. sabrinus are endangered, and thus, interspecific hybridization is a key conservation concern in flying squirrels. We sequenced and assembled a de novo long-read genome from a G. volans individual sampled in southern Ontario, Canada, while four short-read genomes (2 G. sabrinus and 2 G. volans, all from Ontario) were re-sequenced on Illumina platforms. The final genome assembly consisted of approximately 2.40Gb with a scaffold N50 of 455.26Kb. Benchmarking Universal Single-Copy Orthologs reconstructed 3,742 (91.2%) complete mammalian genes, and genome annotation using RNA-seq identified the locations of 19,124 protein-coding genes. The four short-read individuals were aligned to our reference genome to investigate the demographic history of the two species. A Principal Component Analysis clearly separated re-sequenced individuals, while inferring population size history using the Pairwise Sequentially Markovian Coalescent model noted an approximate species split one million years ago, and a single, possibly recently introgressed individual.

Known Range Expansion and Morphological Variation in the Southern Flying Squirrel (Glaucomys volans) in Quebec

New records of the Southern Flying Squirrel (Glaucomys volans) in Quebec expand its known range in the province 150 km east to the appalachian foothills and farther west than previously assumed. We obtained individuals through live trapping, trapper collaboration, and opportunistic discoveries. Species identification was confirmed with morphological traits and molecular analysis. individuals were smaller in the eastern part of the province in terms of mass, total length, and tail length. Some live captures also seem to corroborate the fact that Southern Flying Squirrels are mainly associated with mature hardwood forests.De nouvelles mentions du petit polatouche (Glaucomys volans) au Québec permettent d’étendre son aire de répartition connue jusqu’à 150 km à l’est dans les contreforts des appalaches et plus à l’ouest que présumé. Les spécimens ont été obtenus via des captures vivantes, la collaboration des trappeurs et des découvertes opportunistes. L’identification de l’espèce a été confirmée sur des bases morphologiques et moléculaires. Les individus étaient plus petits dans l’est de la province en considérant la masse, la longueur totale et celle de la queue. Les quelques captures d’animaux vivants semblent corroborer que le petit polatouche est davantage associé, au niveau de l’habitat, aux peuplements de feuillus matures.