Section Auganthus photographs

Section Auganthus (Link) Pax ex Balf.f., J. Roy. Hort. Soc. 39:139. 1913.

Type species P. sinensis Sabine ex Lindl.

P. calciphila Hutch.
P. filchnerae R.Knuth
P. fujiangensis J.L.Gu, Ying F.Hu & S.Y.Zhang
P. jiangyouensis J.L.Gu & Z.K.Wu
P. praenitens Ker Gawl.
--- P. sinensis Sabine ex Lindl. (nom. illeg.)
--- Primulidium sinense Spach (nom. illeg.)
--- Auganthus praenitens (Ker Gawl.) Link
--- P. mandarina Hoffm.
--- P. semperflorens Loisel. ex Steud.
--- P. sertulosa J.Kickx f.
P. rongrong S.Y.Zhang, Y.Hu & J.W.Shao
P. rupestris Balf.f. & Farrer
P. xingshanensis Yu B.Wang

Distinguished by the inflated calyx with a flat base. Leaves pilose, glandular, without farina, pinnatisect, with a distinct petiole. Flowers red to white, heterostylous. Capsule globose, opening by valves.
P. filchnerae is the type species for section Pinnatae R.Knuth. However, it is morphologically similar to other species in section Auganthus, and recent phylogenetic analysis places it in section Auganthus, clustered with P. sinensis. P. praenitens is well known under the name P. sinensis, but that name is illegitimate. See an explanation of this. A proposal to conserve the name P. sinensis has been made but has not yet been accepted at this time. P. rupestris is nearly indistinguishable from P. praenitens and is has been thought it to be a wild progenitor for the cultivated P. praenitens, however genetic studies indicate they are separate species and attempts to hybridize the two species have failed. An excellent figure comparing leaf shapes of P. rongrong, P. fujiangensis, P. sinensis and P. xingshanensis, as well as a key to the species in section Auganthus is given in Zhang et. al. 2025, "Two New Species of Primula Sect. Auganthus From Sichuan, China". P. calciphila is usually described as as synonym of P. rupestris but there is some evidence that it is distinct.

See Hao Gang, Hu Chi-Ming and Lee Nam-Sook. 2002, "Circumscriptions and phylogenetic relationships of Primula sects. Auganthus and Ranunculoides: Evidence from nrDNA ITS sequences"
See Yuan Xu, Yun-Fei Deng, Gang Hao, Chi-Ming Hu. 2020, "(2760) Proposal to conserve the name Primula sinensis Sabine ex Lindl. against P. sinensis Lour. (Primulaceae)"