The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny.
A new subspecies, Primula obconica subsp. fujianensis, is described. The genus Primula is widely distributed throughout China, but it has never been previously recorded in Fujian and Jiangsu. Recently the authors collected a specimen of the genus from Fujian for the first time. It is obviously closely related to P. obconica, which is one of the most common species in China, ranging from western Yunnan and Sichuan through Guizhou, Hubei to Hunan and northern Guangdong, with its most easterly extension in southern Jiangxi. Morphologically, the Fujian plant is characterized by its much smaller stature and by the scapes being shorter than the leaf rosette, and in many ways it is more closely related to P. obconica subsp. parva, but can be easily distinguished by its smaller, white and homostylous flowers. As it is isolated both in distribution and reproduction with other subspecies of P. obconica, here it is described as a new subspecies.
