Research Article |
Corresponding author: Jorge O. Chiapella ( jchiapella@comahue-conicet.gob.ar ) Academic editor: Marcin Nobis
© 2021 Jorge O. Chiapella, Zhi-Qing Xue, Josef Greimler.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Chiapella JO, Xue Z-Q, Greimler J (2021) The genus Deschampsia and the epithet “ alpina”. PhytoKeys 181: 95-103. https://doi.org/10.3897/phytokeys.181.69546
|
The epithet “alpina” has been recurrently used in the genus Deschampsia to name plants located in northern regions of Europe, Asia and North America, as a species (Deschampsia alpina (L.) Roem. & Schult.), but also in infraspecific categories (Deschampsia cespitosa subsp. alpina Tzvel. and Deschampsia cespitosa var. alpina Schur.). The morphological and molecular available evidence suggests the existence of a single species, Deschampsia cespitosa (L.) P. Beauv., in which individuals belonging to the same morphological gradient have received different names in different taxonomic categories throughout its wide distribution range. An evaluation of the available names indicates that all uses of the epithet “alpina” are illegitimate. A new combination is proposed at the infraspecific level as Deschampsia cespitosa subsp. neoalpina Chiapella, Xue & Greimler.
Aira alpina, Deschampsia, Deschampsia alpina, Deschampsia cespitosa var. alpina, Deschampsia cespitosa subsp. alpina
Deschampsia cespitosa (L.) P. Beauv. has a nearly cosmopolitan distribution, being more common in cold temperate regions of the Northern Hemisphere. This extended geographic distribution shows different morphological variants, which have been considered in two alternate ways, either as infraspecific taxa of a widely distributed species (
Taxa delimitation and nomenclatural problems are common in Deschampsia of northern regions of North America, Europe and Asia. The present contribution aims at clarifying the status of the taxon appearing alternatively under the names Deschampsia alpina (L.) Roem. & Schult., Deschampsia cespitosa subsp. alpina Tzvel. and Deschampsia cespitosa var. alpina Schur.
Morphological quantitative characters in Deschampsia cespitosa may vary greatly in short environmental gradients. Plants growing along a 40 m long gradient on tidal soils showed significant differences in plant height and leaf width (
Comparison of selected morphological traits in Deschampsia cespitosa s.l. in North America (left panel) and North Central Europe (right panel): plant height A panicle length B panicle width C ligule length D lower glume length E lemma length F awn length G taxa codes: Deschampsia cespitosa subsp. septentrionalis (s); D. cespitosa subsp. orientalis (o); D. cespitosa subsp. glauca (g); D. cespitosa subsp. neoalpina (n); D. cespitosa subsp. cespitosa (c); D. cespitosa ssp. mackenzieana (m); D. cespitosa ssp. beringensis (b); D. cespitosa ssp. littoralis (l); D. cespitosa subsp. wibeliana (w); D. cespitosa subsp. parviflora (p). Redrawn from
An additional problem in Deschampsia is the development of the sprouting spikelet (glumes, lemmas, paleas), a consequence of the pseudovivipary typical in the taxon named “alpina”. These parts elongate beyond the habitual range of D. cespitosa, eventually becoming plantlets. Pseudovivipary is an asexual reproductive strategy commonly found in grasses, in which plantlets develop from spikelets and detach from the parental plant after development (
Synopsis of cytogenetic information for Deschampsia alpina (L.) Roem. & Schult. (Source:
Count | Distribution | Source |
---|---|---|
2n = 39, 41, 49. | Spitzbergen, Svalbard Archipelago |
|
2n = 56. | Northern Europe |
|
2n = 49. | British Isles |
|
2n = 26, 39, 48, 52 | Northern Europe |
|
2n = 52. | Greenland |
|
2n = 49, 56. | British Isles |
|
2n = 35–38. | Arctic Russia |
|
2n = 39, 52. | Iceland |
|
2n = 49, 49 + 2B. | Greenland |
|
2n = 26, 38–39. | Arctic Russia |
|
2n = 39 + 3 – 4ff, 49. | Northern Norway |
|
2n = 50. | Bear Island, Svalbard Archipelago |
|
2n = 29 49–52. | Europe, northern Africa |
|
The lack of recent cytogenetic studies prevents a comprehensive analysis of the taxon history. However,
The combination Deschampsia cespitosa subsp. alpina (L.) Tzvel. has been deemed an illegitimate homonym (
However, Article 53.3 (
The debates on delimitation of taxa -at specific or infraspecific level- have been recurrent during the 1990’s (
The available information for Deschampsia cespitosa comprises a set of morphological data for Central Europe (
Since molecular data supports the existence of a single entity, but the morphological data shows variation, the treatment as infraspecific entities seems proper. Consequently, and because all available combinations using the epithet “alpina” are illegitimate, a replacement name in reference to Article 41 (
≡ Aira alpina L. Sp. Pl. 65. 1753.
≡ Deschampsia alpina (L.) Roem. & Schult. Syst. Veg. 2: 686. 1817.
≡ Aira alpina Lilj., Utkast Sv. Fl. 49. 1792.
≡ Aira alpina var. vivipara Parn., Grasses Brit.: 242 t. 109. 1845.
≡ Avena alpina (L.) Trin., Fund. Agrost.: 157. 1820.
≡ Aira caespitosa subsp. alpina (L.) Hook. f. Student Fl. Brit. Isl. 3: 437. 1870.
≡ Aira major subsp. alpina (L.) Syme ex J.E. Sowerby, Engl. Bot. (ed. 3B) 11: 65. 1877.
≡ Deschampsia cespitosa (L.) P.Beauv. var. alpina Vasey in Beal, Grasses N. Amer. 2: 368. 1896.
≡ Deschampsia cespitosa subsp. alpina (L.) Tzvel., in Fed., Fl. Evrop. Chasti SSSR 1: 209. 1974.
= Aira alpina Roth, Tent. Fl. Germ. 2(1): 98. 1789.
= Aira laevigata Sm., Engl. Bot. 30: t. 2102. 1810.
= Deschampsia laevigata (Sm.) Roem. & Schult., Syst. Veg. 2: 687. 1817.
= Deschampsia cespitosa var. alpina Schur, Oesterr. Bot. Z. 9: 326. 1859.
= Deschampsia cespitosa var. alpina Gaudin ex Ducommun, Taschenb. Schweiz. Bot, 861. 1869.
= Deschampsia cespitosa var. alpina (Hoppe) Honda (J. Fac. Sci. Univ. Tokyo (1): 139. 1930.
= Aira caespitosa var. alpina Hoppe, Flora: 166. 1817–1823.
= Deschampsia cespitosa var. alpina (Hoppe) Honda, J. Fac. Sci. Univ. Tokyo, Sect. 3, Bot. a3(1): 139. 1930.
= Aira caespitosa var. alpina Gaudin, Fl. Helv. 1: 323. 1828.
= Deschampsia cespitosa var. alpina Gaudin ex Ducommun, Taschenb. Schweiz. Bot. 861. 1869.
= Aira caespitosa var. alpina Heuff. Verhandlungen der Zoologisch-botanischen Gesellschaft in Wien 8: 228. 1858.
= Aira vivipara Steud., Syn. Pl. Glumac. 1: 222. 1854.
= Aira alpina var. vivipara (Steud.) Lange, Consp. Fl. Groenland. 3: 163. 1880.
Sweden, Torne Lappmark, Mt. Njuolja, 25.07.1950, leg. N.D.Simpson 50133 (BM), neotype selected by Cope in Cafferty et al., Taxon 49: 293. 2000.
We thank Walter Till (University of Vienna) for many useful discussions on the Code of Nomenclature. Joseph C. Kuhl (University of Idaho) read the manuscript, making valuable suggestions. This research was supported by the Austrian Science fund (FWF grant P30208-B-29 to J.G. and J.O.C.) and the China Scholarship Council (CSC) by grant NSCIS 201804910630 to Z-Q.X.