(2677) Proposal to conserve the name Bromus inermis (Poaceae: Bromeae) with a conserved type

Résumé fourni par la source

(2677) Bromus inermis Leyss., Fl. Halens.: 16. Jan 1761 [Angiosp.: Gram.], nom. cons. prop. Typus: Germany, Bayern, Oberbayern, Landkreis Fürstenfeldbruck, westlicher Ortsrand von Gröbenzell, neben dem Fahrradweg entlang der Strasse nach Olching, 25 Mai 2010, Kress (LEB barcode LEB121816!), typ. cons. prop. The awnless brome currently known as Bromus inermis Leyss. (smooth bromegrass, Russian brome) is native from Europe eastwards to China. It is introduced in some European countries, North America, South America, Africa, Australia, and New Zealand (Bromus inermis in: Plants of the World online. 2018; http://www.plantsoftheworldonline.org/). It is one of the most important agricultural species, used as fodder, being among about 10 species in the genus used in agriculture (Williams & al. in Kole, Wild Crop Relatives: Genom. Breed. Resources; Millets & Grasses: 15–30. 2011). It is well represented in most herbaria from Asia, Europe, and North America. Its importance is corroborated by 24,800 Google Scholar results when searching the string “Bromus inermis” (on 21 Mar 2019). Its name is proposed for conservation to maintain a name in current use in many countries all over the world. The current widespread use of this name may be illustrated by its presence in numerous national, regional, and local floristic publications. It appears under Bromus L. or combined under the genera Bromopsis (Dumort.) Fourr., Forasaccus Bubani, Festuca L., and Zerna Panz. It appears in frequently consulted floras such as Flora of North America (Pavlick & Anderton in Flora of North America Editorial Committee, Fl. N. Amer. 24: 193–237. 2007), Flora of China (Liu & al. in Wu & Raven, Fl. China 22: 371–386. 2006), and most European floras or monographs (Fiori, Nuov. Fl. Italia 1: 145–150. 1969; Hegi, Ill. Fl. Mitt.-Eur. 1: 355–369. 1908; Tzvelev, Zlaki SSSR: 298–340. 1976; Acedo & Llamas in Phanerog. Monogr. 22: 245. 1999; Cope & Gray, Grass. Brit. Isles: 444. 2009) or the ongoing Flora iberica (unpub. results), which will include it among the naturalized species of this genus. Leysser (Fl. Halens.: 16. 1761) described this perennial Bromus as having muticous lemmas and being from Germany. He asserted that it was living “in pratis succulentis fertilissimis im Fürstengarten; in den Pulverweiden frequens” in Germany, and cited “Scheuchz. hist. 266. t. 5. f. 18” [J. Scheuchzer, Agrostographia: 266, t. 5, fig. 18. 1719]. Later Leysser (Fl. Halens., ed. 2: 25. 1783) extended the locality indication for Bromus inermis to “in pratis fertilibus succulentis Pomariis, in den Pulverweiden, im Amtsgarten ad Belberg, ad Crôllwitz et alibi frequens; Iunio, Iulio”. Some specimens or types of the Leysser herbarium are preserved at LINN (Stafleu & Cowan in Regnum Veg. 98: 870. 1979), and Cope (in Nasir & Ali, Fl. Pakistan 143: 575. 1982) indicated for this species that the type is in LINN. Saarela (in J. Bot. Res. Inst. Texas 2: 339. 2008) asserted that Leysser s.n. in LINN is the holotype and later, Saarela & al. (in Phytotaxa 185: 96. 2014) indicated the holotype of Bromus inermis Leyss. to be in S (S-LINN). A detailed study of Bromus specimens in these collections revealed that there is no Leysser material, nor any material of German origin. A specimen preserved at LINN (No. 93.13) bears the handwriting by Linnaeus “inermis ex descr.”, but it also has the annotation “H.U.” meaning that the plant was grown in Hortus Upsaliensis, so it cannot be original material of Leysser. At the Linnean Society of London, there is a post 1761 manuscript by Carl von Linné, entitled “Plantae Halenses nobis exoticae” (http://linnean-online.org/143626/). This indicates that Linnaeus received material of the Halensis flora after Leysser's publication appeared. Bromus inermis is among the species listed, so perhaps LINN No. 93.13 cited above has that origin and was cultivated from seeds. As noted, our search for these quoted specimens in LINN and S did not turn up any specimen of this taxon collected or reviewed by Leysser. Therefore, the only remaining original material is the illustration of Scheuchzer that Leysser cited in the protologue. This illustration shows a fragment of the inflorescence, a branch of a grass having short spikelets and awned lemmas that does not reasonably represent Bromus inermis Leyss., and seems to represent a species of Festuca. Because no other original material is available, if we choose as lectotype the illustration of Scheuchzer, the name B. inermis should be applied to a different species, and we would have to use B. confinis Nees (in Steudel, Syn. Pl. Glumac. 1: 320. 1854 [‘1855’]) for the important agricultural species. However, for the purpose of nomenclatural stability and to support the continued and well-established use of the name B. inermis we here propose its conservation with a conserved type under Art. 14.9: Germany, Bayern, Landkreis Fürstenfeldbruck, westlicher Ortsrand von Gröbenzell, neben dem Fahrradweg entlang der Strasse nach Olching, 25 May 2010, Alarich Kress, LEB barcode LEB121816(!). Rejection of this proposal would mean that the established application of B. inermis would need to be abandoned, as the original material for B. inermis is referable to another species and even to a different genus. Another name would need to be taken up for what is currently called B. inermis. This would be undesirable because of the negative impact it would entail to nomenclatural stability. CA, https://orcid.org/0000-0001-6692-6509; FL, https://orcid.org/0000-0002-2218-896X Thanks are due to the staff of the herbaria consulted to help us find materials, and to Mrs. Amelia Llamas for proofreading the paper and English language editing. We are also very grateful to John Wiersema and Robert Soreng for their critical comments and helpful suggestions, and John McNeill for several editorial improvements. This work was supported by the Spanish “Ministerio de Economía y Competitividad MICINN” under Flora Iberica IX Grant CGL2011-28613-C03-03, and Flora Iberica X Grant CGL2014-52787-C3-1-P.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.