Allium ekimianum: a new species (Amaryllidaceae) from Turkey

Abstract Allium ekimianum is described here as a new species. This taxon belongs to the genus Allium section Allium and grows in Elazığ Province (East Anatolia, Turkey). It is a narrowly distributed species and morphologically most similar to Allium asperiflorum and Allium sintenisii, and Allium erzincanicum but it is clearly differentiated due to the curved stem, smooth pedicel surfaces, bracteole arrangements at pedicel bases, tepal lengths and surfaces. In this study, a comprehensive description, distribution map of Allium ekimianum, identification key, and detailed illustrations are provided for Allium ekimianum and related taxa.


Introduction
Th e genus Allium L. is one of the largest monocotyledonous genera with c. 900 species distributed world-wide (Govaerts et al. 2013, Keusgen et al. 2011. Th e genus was formerly included in the Liliaceae family, but the Angiosperm Phylogeny Group (APG) reassessed the taxonomic position of this genus and fi nally Allium was placed in the Amaryllidaceae family (APG III 2009). Th e primary evolution center of the genus extends across the Irano-Turanian biogeographical region, and the Mediterranean basin and western North America are secondary centres of diversity (Friesen et al. 2006).
Based upon these centres, Allium species have scattered widely all over the northern hemisphere (Hanelt 1990, Fritsch andFriesen 2002). Th e genus is characterized by having bulbs enclosed in membranous (sometimes fi nally fi brous) tunics, terminal umbel, free or almost free, 1-veined tepals, often a subgynobasic style and loculicidal capsule with one or two seeds per loculus (Kollmann 1984).
Following the results of recent molecular investigations, Allium is divided into 15 subgenera and 56 sections (Friesen et al. 2006). Subgenus Allium is the largest, comprising approximately 280 species (Hanelt et al. 1992), 114 of which compose its largest section, Allium (Mathew, 1996). Section Allium encompasses those species of Allium that have a well-developed bulb, stem (never basal) leaves, campanulate to cupshaped (never stellate) fl owers, and fi laments in two distinct whorls, the outer three nearly always simple and the inner three markedly tricuspidate (rarely 5-7 cuspidate) with the anther attached to the median cusp. Th is section includes economically important species, such as garlic (A. sativum L.) and leek (A. ampeloprasum L.), as well as other minor crops of local importance, such as great headed garlic, and kurrat (Block 2010). Despite the major importance of the section Allium, it has not been subjected to a comprehensive molecular taxonomic evaluation; only partial molecular genetic studies that involved a limited set of species have been published (Kik et al. 1997;Havey and Leite 1999;Bohanec et al. 2005;Hirschegger et al. 2010). Interspecifi c and infraspecifi c relationships within this section still remain unresolved. As reviewed by Mathew (1996), polyploidy is a common feature in section Allium. However, to a certain extent, it has been left unexplored, leaving the origin of polyploid species undetermined (Hirschegger et al. 2010).
Turkey has approximately 190 Allium taxa in 14 sections, c. one-third endemic, demonstrating that it is a prominent part of the southeastern Asian center of Allium diversity (Ekşi et al. 2015;Özhatay and Kandemir 2015;Koyuncu 2012). Section Allium remains the most species-rich section of the genus (Friesen et al. 2006).
Turkey has four reasons for having an exceptionally rich fl ora. First, it is the meeting point of three phytogeographical regions, the Euro-Siberian, Mediterranean and Irano-Turanian regions. Second, Anatolia (Asian part of Turkey) is a passageway and a migration route between Southern Europe and the fl ora of South-West Asia allowing the penetration of Asiatic elements into South Europe. Th ird, many taxa have their center of origin and/or center of diversity in Anatolia. Fourth, the endemism ratio is high, presumably connected with the climatic and topographical diversity of the country (Davis 1965(Davis , 1971. During the revision of the treatment of Allium in Turkey, individuals of a new species were collected by Prof. Dr. Mehmet Koyuncu in 1983 from Eastern Anatolia. Th ey belong to Allium section Allium due to ovoid bulb, linear leaves, campanulate to ovoid perigon; 3-cuspidate inner fl aments, distinct nectariferous pores on ovary, ovule numbers in per loculus (Kollmann 1984). Th e initial evaluation suggested this collection was a form of A. asperifl orum Miscz. However, detailed examination of herbarium material and a review of the literature indicated this represented an undescribed species. Th e present study is focused on the morphological characters for distinguishing a new species in Allium section Allium. Investigations on living and herbarium specimens suggest that this new species is morphologically most similar to A. asperifl orum, A. erzincanicum N. Özhatay & Kandemir and A. sintenisii Freyn.

Materials and methods
Th e overall morphology of the new species was examined by stereo binocular microscope (Leica Zoom 2000). For morphological comparisons, we consulted dry herbarium material kept in AEF, ANK, E, GAZI, and ISTE (acronyms according to Th iers 2015). Th e Flora of Turkey and fl oras of the neighbouring regions including Iran, Iraq, and Syria were also consulted (Boissier 1882, Feinbrun 1948, Wendelbo 1971, 1985, Kollmann et al. 1983, Kollmann 1984, Mathew 1996, Özhatay and Tzanoudakis 2000. Th e diagnostic traits of the new species and its three most similar relatives are presented in Table 1. Distribution map of compared taxa is provided according to the Grid classifi cation system developed by Davis (1965) in Figure 1. IUCN conservation assessment and justifi cation is proposed according to the criteria established by IUCN (IUCN 2003). In addition, an identifi cation key is provided to distinguish new species and closely related taxa.
Description. Bulb ovoid, 0.7-1.2 × 1-1.5 cm; outer tunics membranous, brownish, ± breaking into parallel fi bres; inner tunics white; bulblets absent. Stem 15-35 cm, curved, often purplish below. Leaves 2-3, linear, 1-2 mm broad, fl at, shorter than scape, sheathing lower ½ of stem. Umbel globose-subglobose, 1.5-3 cm diameter, dense, 20-60 fl owered. Spathe caducous. Pedicels smooth, unequal, not elongating in fruit; up to 2.5 × perigon; bracteoles present, united at the base of outer pedicels, splitting into several lobes at apex, c. 5 mm. Perigon ovoid, campanulate; tepals purple, pale pink; outer tepals straigth, 5 × c. 3.5 mm, obovoid, verrucose-scabrid, acutesubacute, obtus at apex; inner tepals c. 4 × 2 mm, narrowly oblong, smooth, obtus at apex. Stamens included; fi laments ciliate at base; inner fl aments 4 × 2 mm; median cusps c. 1 mm, slightly shorter than lateral cusps (c. 1.5 mm); basal lamina c. 3 mm, 3 Distribution and ecology. Th e distribution of Allium ekimianum is restricted to Province of Elazığ from East Anatolia, where it grows on steppe between 1100-  scorodoprasum L., Vicia cracca L., Crepis foetida L., Eryngium campestre L., Salvia verticillata L., Avena sterilis L. Elazığ is located on the east of Anatolian diagonal, in the skirts of South-Eastern Taurus Mountains (Çakılcıoğlu et al. 2008), in the Upper Euphrates Region of the Eastern Anatolia Region (Şengün 2007). Elazığ belongs to the Irano-Turanian Plant Geography Region and falls within the B7 grid square (Davis 1965). Th e Irano-Turanian Region is confi ned to Central and East Anatolia. Th is great region of steppe, mountain steppe and semi-desert is also characterized by the existence of a hypothetical oblique line that runs from Bayburt-Gümüşhane southwestwardly to Anti-Taurus where it bifurcates with one prong leading to the Amanus and the other to the Cilician Taurus. Th is line is called "Anatolian Diagonal" (Figure  1). Th e fl ora of central Anatolia as the western side of the Diagonal is fl oristically different from the rest of the Irano-Turanian region to the east. According to the plant distribution patterns in eastern Anatolia, many endemics are restricted to part of the Diagonal belt, or extend right along it (Davis 1965, Davis 1971. IUCN Conservation Assessment and Justifi cation. Following the criteria established by IUCN (IUCN 2003), an initial provisional assessment of Critically Endangered (CR) (criteria B2a + B2biii) is suggested for this new taxon. Th is species occurs only in Elazığ University campus area in Elazığ province (East Anatolia) at 1100-1200 m. Th e area is under subversive people activities such as new constructions of buildings. As a result, the habitat of Allium ekimianum is highly threatened of vanishing by people activities. Th e area of A. ekimianum occupancy (AOO) is less than 10 km 2 with the number of mature individuals which is under reduction and being less than 50.
Related species. Allium ekimianum is closely related to A. asperifl orum and A. sintenisii and A. erzincanicum. All four species share traits of ovoid bulb, globose to subglobose umbel, campanulate to ovoid perigon, rough outer tepal surfaces, stamens sorter than perigon, ovoid ovary. Allium ekimianum diff ers from A. asperifl orum, A. sintenisii and A. erzincanicum in its outer tunics, stem, leaves, bracteoles, pedicel surface, outer tepal, and inner tepal characters. Th e three species are compared in Table 1 and these traits are illustrated in Figures 2-4.

Additional specimens examined
Th e capital letters and the numbers in bold after species names represent the Grid classifi cation system (Davis, 1965)