Resurrection of Stipatremula and taxonomy of the high-alpine species from the Stipapurpurea complex (Poaceae, Pooideae)

Marcin Nobis; Marta Krzempek; Arkadiusz Nowak; Polina D Gudkova; Ewelina Klichowska

doi:10.3897/phytokeys.196.82598

Resurrection of Stipatremula and taxonomy of the high-alpine species from the Stipapurpurea complex (Poaceae, Pooideae)

PhytoKeys. 2022 May 13:196:21-47. doi: 10.3897/phytokeys.196.82598. eCollection 2022.

Authors

Marcin Nobis¹, Marta Krzempek¹, Arkadiusz Nowak^{2

3}, Polina D Gudkova^{4

5}, Ewelina Klichowska¹

Affiliations

¹ Institute of Botany, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland Jagiellonian University Krakow Poland.
² Institute of Biology, University of Opole, 45-052 Opole, Poland University of Opole Opole Poland.
³ Botanical Garden, Center for Biological Diversity Conservation, Polish Academy of Sciences, 02-976 Warszawa, Poland Center for Biological Diversity Conservation, Polish Academy of Sciences Warsawa Poland.
⁴ Research Laboratory 'Herbarium', National Research Tomsk State University, Lenin 36 Ave., 634050 Tomsk, Russia Tomsk State University Tomsk Russia.
⁵ Institute of Biology, Altai State University, Lenin 61 Ave., 656049, Barnaul, Russia Altai State University Barnaul Russia.

Abstract

Stipapurpurea is a high-alpine species that occurs in cryophilous steppes, semi-deserts and stony slopes, from the Tian Shan and Pamirian Plateau through Qinghai-Xizang Plateau to the Himalayas and is characterised by a great morphological variability. During the revision of specimens of the taxon, we observed that the pattern of this variability is linked to the geographical distribution of the specimens. Numerical analyses (PCA and UPGMA) revealed three groups of OTUs corresponding to three morphotypes within the S.purpurea complex. A set of macro- and micromorphological characters, supported by a map of general distributional ranges, are presented to distinguish each of the three taxa within the complex and we reassess the status of Lasiagrostistremula described by Ruprecht in 1869. As a result, Stipatremula, S.purpurea and S.arenosa were distinguished within the complex. The intermediate characters of S.arenosa may suggest its putative hybrid origin (S.tremula × S.purpurea), whereas the presence of extremely long florets may be an expression of the gigas effect. We propose two new combinations (S.tremula and S.arenosa), describe a new nothospecies (S.×ladakhensis) that originated from hybridisation between S.klimesii and S.purpurea s.l. and designate the lectotype for Ptilagrostissemenovii. An identification key and detailed morphological description of species from the S.purpurea complex are also presented.

Keywords: Lasiagrostis; Ptilagrostis; distribution; feathergrasses; hybridisation; micromorphology; taxonomy; typification.

Marcin Nobis, Marta Krzempek, Arkadiusz Nowak, Polina D. Gudkova, Ewelina Klichowska.