Primula shimokitana (Primulaceae): A New Species from the Northernmost Honshu Island, Japan

Reexamination of the primrose on the Shimokita Peninsula, northernmost Honshu, Japan, which has been treated as Primula modesta Bisset & Moore showed that it is closely related to P. sorachiana Miyabe & Tatew., endemic to Hokkaido, based on morphology and phylogenetic investigations. However, it can be distinguished from P. sorachiana by its smaller stature, flowering scape shorter than leaves, base of bracts non-saccate, larger and fewer flowers, and shallowly parted calyx lobes. Based on the results, the plants from the Shimokita Peninsula are described as a new species, P. shimokitana Mas. Yamam.