Nomenclatural Notes on Allium atroviolaceum (Amaryllidaceae) from Iran

Abstract

Allium is one of the largest genera of the family Amaryllidaceae which is approximately distributed in all parts of the world. Iran is one of the main centers of diversity of the genus Allium and 7 subgenera and 30 sections are considered from this genus for the flora of Iran. In spite of taxonomic and phylogenetic studies, there are a few nomenclature studies regarding the genus Allium. The present study is the result of the exact checking of the species Allium with the International Code of Nomenclature. It was established that Allium atroviolaceum Boiss. (1846) is an illegitimate name as a later homonym of Allium atroviolaceum Hornem. ex Steud. (1840). So, the name Allium sehat-niakii Negaresh nom nov. is proposed here as a replacement name for Allium atroviolaceum Boiss. Also, a note about the previous typifications of Allium atroviolaceum is presented. In addition, it is indicated that Allium atroviolaceum var. angustifolium Boiss. is a forgotten taxon for Iranian flora and it is treated in this study as an existing taxon with the new combination (i.e. Allium sehat-niakii var. angustifolium (Boiss.) Negaresh) for the flora of Iran.Key words: Allium, Flora Iranica, Taxonomy, Lectotype. IntroductionAmaryllidaceae is one of the largest families in the monocot plants, having about 75 genera and 1600 species, distributed in tropical to subtropical areas of the world. The genus Allium L., comprises about 900 species, distributed all over the world with the main center of diversity in Southwest Asia, especially Iran. In this regard, 7 subgenera and 30 sections are considered from this genus for the flora of Iran. The nomenclatural study of the genus Allium showed that Allium atroviolaceum Boiss. (1846) based on the International Code of Nomenclature (ICN) is an illegitimate name, because it is a later homonym of Allium atroviolaceum Hornem. ex Steud. (1840). In this research, in order to clarify the use of this taxon, a valid name is proposed for it and a note on its typification is presented. In addition, it was indicated that Allium atroviolaceum var. angustifolium Boiss. is a forgotten taxon for the Iranian flora. Materials and MethodsThe purpose of the international rules of plant nomenclature is to organize past nomenclature and provide rules for the future. According to these rules, opposing names cannot be preserved. In the present study, according to the mentioned rules, the species of the genus Allium were examined in terms of compliance with the nomenclature rules. The present nomenclature study was based on the latest international botanical meeting held in Shenzhen, China in 2018, and the result was the 19th "International Code of Nomenclature" published by Turland et al. in 2018. Results and ConclusionThe name Allium atroviolaceum was first published by Steudel in 1840. Later, Boissier (1846) published a species under the same name. According to the International Code of Nomenclature (Art. 53.1; Turland et al. 2018), the name used by Steudel is legitimate and Allium atroviolaceum Boiss. is an illegitimate later homonym. The replacement name Allium sehat-niakii is therefore published here. When Boissier described Allium atroviolaceum var. angustifolium in 1854, he cited a type locality for it: prope urbem Tehran, Kotschy 449. According to the location of the type mentioned in the protologue, the variety angustifolium is distributed in Iran.The type specimens observed by the authors confirm that the two specimens collected by Kotschy from Iran are present in the herbariums of Geneva (G) and Paris (P). Therefore, Allium atroviolaceum var. angustifolium is a variety reported for the flora of Iran, which Wendelbo (1971) ignored in Flora Iranica, and here it is reported again for the flora of Iran. Var. angustifolium differs from the var. atroviolaceum by having narrower leaves. In the present research, the angustifolium variety is transferred to Allium sehat-niakii. With this rediscovery, the species A. sehat-niakii includes two varieties: var. sehat-niakii and var. angustifolium. Boissier described Allium atroviolaceum in 1846 based on the collection of Kotschy 450. During a review of various herbariums, it was found that fourteen plant samples belong to Kotschy 450 (BM000958288, FI012000, G00164986, G-DC (G00164987), G00164988, GOET000718, K000464376, L0041350, LE00010808, LE00010809, MO-149473, P00601093, P00601092, and P00747749). In Flora Iranica, the specimen of G herbarium is considered as the type. Meanwhile, there are three specimens related to Kotschy 450 collection (G00164986, G-DC (G00164987), G00164988) in G herbarium. Khorasani et al. (2018) considered the specimen G00164986 as lectotype, but did not pay attention to the fact that Allium atroviolaceum was previously typified by Wendelbo (1971), albeit incompletely. Therefore, based on the International Code of Nomenclature (Art. 9.15), the typification of Wendelbo (1971) should be considered as the lectotype determination in the first step and the typification of Khorasani et al. (2018) as the lectotype determination in the second step.

Keywords

• allium
• flora iranica
• taxonomy
• lectotype