Allium serpenticola Eker, 2024

Eker, İsmail, 2024, Allium serpenticola (A. sect. Codonoprasum, Amaryllidaceae), a new species from Türkiye, Phytotaxa 634 (2), pp. 120-130 : 121-128

Allium serpenticola Eker sp. nov. ( Figs. 1–5 ).

Allium serpenticola is partly similar to A. stamineum (both s.str. and s.l.) for its habitus, but it is easily distinguished from the latter species (see also Table 1) by its spathe valves shorter than umbel (vs. both or at least one of the valves longer than umbel), dark reddish-maroon and glaucous (vs. purplish-pink, pink, greenish-yellow tinged with purple to whitish) perigone, dark reddish-maroon (vs. greenish-pink, greenish-purple to pink or purplish-pink) pedicels, mauve (vs. yellow) anthers, shorter filaments and their ratio to the perigone (4–5 mm long, 1.12–1.25 × as long as the perigone vs. 4–7 mm long, 1.25–1.5 × as long as the perigone), anther size (0.7–1 × 0.3–0.6 mm vs. 1–1.5 × 0.8–1 mm), constant style length (3–4 mm long vs. (1–) 2–7 mm long), 2 leaves shorter or as long as the stem (vs. 3–4 leaves longer or shorter than the stem), proportion of sheats surrounding scape (1/3–1/2 vs. 1/2–2/3), brown (vs. pale ash-gray, pale ash-brown or dark brown) outer tunics, and seed ornamentation (see Fig. 5 and Table 2).

Type:— TÜRKİYE. Kayseri: Tomarza, Kızıldağ , between Çayinli and Üçkonak Villages, serpentine mountain slopes, 1907 m of elevation, 12 July 2023, İ. Eker 13497 (holotype AIBU!; isotype AIBU!) .

Paratype:— TÜRKİYE. Kayseri: Tomarza, Kızıldağ, between Çayinli and Üçkonak Villages, serpentine mountain slopes, 1841 m of elevation, 12 July 2023, İ. Eker 13520 (in fruit) ( AIBU!).

Bulb ovoid, 10–15 × 8–12 mm, without bulblets; outer tunics coriaceous, brown, and inner ones membranous, whitish. Scape 17–24 cm × 1–1.5 mm, flexuous, slender, cylindrical, striate, glabrous, dull green, covered by leaf sheaths for 1/3–1/2 of its length. Leaves 2, cylindrical, fistulose, ribbed, glabrous, 15–20 cm × c. 1 mm, shorter or as long as stem, withered before flowering. Spathe persistent, bivalved, valves unequal, opposite and often reflexed, narrowly lanceolate to linear-lanceolate, shorter than umbel, the larger 3 or 5-nerved and 11–19 mm long, the smaller 3-nerved and 10–17 mm long. Umbel 3.5–5 cm diam, usually many flowered (15–45-flowered), lax, effuse, without bulbil; pedicels slender, unequal, 5–25 mm long, nodding and become erect during fruiting, dark reddish-maroon. Perigone campanulate, tepals dark reddish-maroon, glaucous, almost equal, 3.5–4 × 1.5–2 mm, the outers elliptic-oblong, subacute, and the inners elliptic-oblong, subacute. Stamens moderately exserted; filaments simple, subulate, reddish-pink on top and gradually turning white towards the base, 1.12–1.25 × as long as perianth, outer filaments 4.5– 5 mm long, the inners 4–4.5 mm long, connate at base into an annulus c. 1 mm high; anthers mauve before dehiscence, oblong, rounded at the apex, 0.7–1 × 0.3–0.6 mm. Ovary elliptic-ovoid, stipitate in the early stage, sessile in the late stage after pollination, rugose-papillose, green, c. 2.5 × 2 mm; style whitish, filiform, sometimes uncinate, 3–4 mm long, protruding, stigma punctiform. Capsule globoid-trigonous, green, 3.5–4 × 3.5–4 mm; seeds 3–3.25 × 1.5–1.75 mm, trapezoidal to hemispheroid shaped, surface shriveled and alveolate in outline, black.

Phenology: Flowering and fruiting in July.

Etymology: —The new species is named after the habitat (serpentine rocks) in which it lives.

Turkish common name of the new species: — Allium is called “ Soğan ” in Turkish. The author proposes “ Tomarza soğanı ” as a vernacular name for A. serpenticola according to the guidelines of Menemen et al. (2016).

Distribution and habitat: —The new species is exclusive of Tomarza, which is located within the borders of Kayseri province in the Central Kızılırmak section of the Central Anatolian region ( Fig. 6 ). It is surrounded by Pınarbaşı and Sarız to the east, Develi to the west, Talas and Bünyan to the north and the Tahtalı branch of the Taurus Mountains to the south and southeast. The area is located in the Irano-Turanian floristic region, where Allium serpenticola , a serpentine-dependent species, only occurs on serpentine rocks at 1500 to 2000 m of elevation.

Species conservation assessment: — Allium serpenticola is known from a single locality: according to criterion B ( IUCN 2022), both its extent of occurrence (EOO) and area of occupancy (AOO) do not exceed an area of 25 km 2. A very high density of adult individuals was observed in this area. Although the distribution of the new species is in a mountainous area, there are four villages in the immediate vicinity and it is located along both villages and district connection roads. In addition, ongoing grazing activities were observed in the area. A decline in habitat quality and EOO/AOO is predicted for the future. The species is therefore assessed as ‘Endangered’ (EN) (criteria B2ab [i, ii, iii]) ( IUCN 2022).

Seed testa micromorphology of close Allium species: —The seed of Allium serpenticola markedly differs from the seed of A. stamineum s.l. in the shape and micro-sculpturing of testa. In particular, A. serpenticola seed shows a trapezoidal to hemispheroidal (vs. hemispheroidal) shape, with periclinal wall ± flat, irregularly granulose (vs. convex, irregularly verrucous), and anticlinal wall fissured, more or less irregularly denticulate-undulate (vs. depressed, curved, covered by strap-like sculpture) ( Fig. 5 ).

Barthlott (1981), based on SEM examinations of about 5000 seeded plants, reported that seed epidermal characteristics were less affected by environmental conditions and were very useful in interspecific and familial classifications. Furthermore, some previous studies ( Bednorz et al. 2011, Celep et al. 2012, Baasanmunkh et al. 2021) have shown that the shape and features of the anticlinal and periclinal walls were quite powerful tools for distinguishing Allium taxa at the interspecific and infrageneric levels. Here, the surface ornamentation of seeds was also found to be highly distinctive for each taxon examined ( Fig. 5 , Table 2).

Taxonomic relationships: — Brullo et al. (2007) suggested that the centre of speciation of A. stamineum group is the Anatolian peninsula, where the highest number of different taxa and populations are concentrated, expanding westward into the Balkan peninsula and eastward into the Iranian territories, where many other taxa occur. In particular, the populations of Allium stamineum group are usually linked to conservative and arid habitats, such as rocky places, cliffs, garrigues, meadows, open pinewoods and salt marshes. Brullo et al. (2007) restricted Boissier’s description of A. stamineum , given as in a wide range of variation and geographical range, and suggested that this species is restricted to Southern and Western Anatolia. Subsequently, many new species belonging to A. stamineum group were described from Anatolia, the Middle East, and eastern Europe such as Allium croaticum Bogdanović, Brullo, Mitić & Salmeri (2008: 107) from the Balkans, Allium garganicum Brullo, Pavone, Salmeri & Terrasi (2009: 79) from Italy, Allium carlstroemi Cattaneo (2020: 105) from the Symi Island, Allium sultanae-ferhanii Balos (2022a: 186) from Türkiye, etc.

However, it should be recognised that the geographical limits and range of variation of the species are not fully resolved by restricting A. stamineum (s.str.) to Southern and Western Anatolia. The observations and analyses I have obtained so far in the populations of A. stamineum suggest that the species is more widespread and more variable than proposed by Brullo et al. (2007). The aim of this paper is not to resolve the A. stamineum species complex. However, to provide a clear view, the new species was compared with both the narrow and the broad concept or A. stamineum .

Allium serpenticola is a species that clearly differs from both A. stamineum s.str. or s.l. for its ecological requirements and for many morphological features ( Tables 1–2).

Selected specimens examined: — Allium stamineum s.l. TÜRKİYE. Caria, 1843, C. Pinard s.n. ( BM 000958297 [!]), G 00165163 [!], G 00165164 [!], G 00165165 [!], G 00165166 [!], K 000464390 [!], P 00748000 [!], P 00748001 [!], P 00748002 [!]), (syntypes of A. stamineum Boiss. ) ; Mersin: Village de Bouloukli , a 2 lieues au nord de Mersina, Cilicie, 3 June 1855, B. Balansa 813 ( JE 00002270 [!], K 000464374 [!], K 000464391 [!], P 00747995 [!], P 00747996 [!]), (syntypes of A. stamineum Boiss. ) ; Bolu: 2 km from Tetemeçele Village to Çaltepe-Çeletepe , roadside, 1225 m of elevation, 23 July 2015, İ. Eker 7174 ( AIBU!) ; Çaltepe, Sarımustan, 7 km from Gurbettaşı to Sarımustan , stony slopes, 1264 m of elevation, 03 September 2016, İ. Eker 11619 (in fruit) ( AIBU!) ; Mengen, 7 km from Yedigöller to Mengen , rocky places, 487 m of elevation, 20 June 2012, İ. Eker 2965 ( AIBU!) ; Mengen, 47 km from Bolu to Mengen , roadside clearing, 527 m of elevation, 14 July 2015, İ. Eker 5676 ( AIBU!) ; Mengen road, 8th km on the way to Mengen, around Saray Village , around the cemetery, 574 m of elevation, 14 July 2015, İ. Eker 5681 (in fruit) ( AIBU!) ; Yedigöller, 6 km from Yedigöller to Bolu, rocky places, 1269 m of elevation, 12 July 2012, İ. Eker 3009 ( AIBU!) ; Yedigöller, Above Anıtçam , rocky areas in the forest, 1215 m of elevation, 10 July 2013, İ. Eker 3596 ( AIBU!) ; Malatya: 10 km from Darende to Akçadağ , barren and clayey hills by the roadside, 1021 m of elevation, 01 July 2016, İ. Eker 10400-b ( AIBU!) ; Şanlıurfa: Bozova, Atatürk Forest , among pine trees, 500–600 m of elevation, 21 May 2002, İ. Eker 362 ( AIBU!) ; Harran University Osmanbey Campus, 20 May 2002, İ. Eker 228 ( AIBU!) ; IRAN. Ghilan Persiae borealis, Aucher Eloy 5387 ( BM 000958295 [!]), K 000464375 [!], P 00747997 [!]), (syntypes of A. stamineum Boiss. ) ; SYRIA. Pl. Alepp. Kurd. Moss. Ed. Hohenacker, 20 May 1841, T. Kotschy 234 ( HAL 0140217 [!], K 000464388 [!], K 000464389 [!]), (syntypes of A. stamineum Boiss. ) ; LEBANON. Iter Syriacum, 1855, T. Kotschy 767 ( P 00747999 [!]), (syntype of A. stamineum Boiss. ) ; Saida, premières collines du Liban entre Hallalie et Baramie , 12 May 1854, C. Gaillardot s.n. ( JE 00002271 [!]), (syntype of A. stamineum Boiss. ) .

Figures

FIGURE 1. Allium serpenticola. a–b: habit, c–d: inflorescence, e: early fruiting period (photographed by İ. Eker).

FIGURE 2. Allium serpenticola. A: habit, B: inflorescence, C: spatha valves, D: cross-section of the leaf, E: longitudinal cross-section of the leaf and the scape, F: lateral view of the perigone, G: internal view of the perigone with stamens in a dissected flower, H: external view of the outer tepal, I: external view of the inner tepal, J: pistil, K: seed, L: capsule [illustrated by H. Yeniceli; Collection no: İ. Eker 13497 (in flower), İ. Eker 13520 (in fruit)].

FIGURE 3. Allium stamineum s.l. a–b: habit, c–f: inflorescence (Coll. no: İ. Eker 5681, 3009, 2965, 7174, 3596, 5676 respectively) (photographed by İ. Eker).

FIGURE 4. Perigon of related taxa. a–c: A. stamineum s.l. (Coll. no: İ. Eker 5681, 5676, 7174 respectively), d: A. serpenticola (Coll. no: İ. Eker 13497). (photographed by İ. Eker).

FIGURE 5. Seed shape (LM) and testa micromorphology (SEM) of Allium serpenticola (a–d, Coll. no: İ. Eker 13520) and A. stamineum s.l. (e–h, Coll. no: İ. Eker 5681).

FIGURE 6. Distribution map of Allium serpenticola (red star), A. stamineum s.l. selected specimens examined (blue circles), and records of the “Flora of Turkey (Kollmann 1984)” (green circles) in Türkiye.