Centaurea malatyensis Ş. Kültür, 2016

Kültür, Şükran, Bona, Mehmet & Nath, Ebru Özdemir, 2016, A new species of Centaurea (Asteraceae) from East Anatolia, Turkey, Phytotaxa 247 (1), pp. 85-91 : 86-89

Centaurea malatyensis Ş. Kültür & M. Bona, sp. nov. ( Figs. 1 , 2 ).

Type: — TURKEY. Malatya: Doğanşehir-Eskiköy, Aşipınar area, rocky places, 1960 m, 10.07.2012, Ş. Kültür et al. (holotype: ISTE 98931!).

Diagnosis: — Centaurea malatyensis is related to C. leptophylla , from which it differs mainly in its stem height 7–15 cm (not 25–35 cm); basal leaves short petiolate, oblanceolate, 5–6 mm wide, entire, tomentose to villous (not sessile, with scabrid margin, glabrous); median and upper leaves with entire margin (not scabrid margin); involucre 37–47 × 12–17 mm (not 0.9–12 × 13–18 mm); phyllary appendages villous in upper part (not glabrous); inner phyllaries 24–27 × 3–5 mm (not 11–13 × 2–3 mm), spinule length 2–3 mm (not 1–2 mm); achenes 6–6.5 × 3.5–4.5 mm, obovoid, brown, pilose (not 4.5–5 × 2.5–3.5 mm, linear-lanceolate, creamy, subglabrous); pappus simple, 18–22 mm long, plumose, brownish (not absent).

Description: —Perennial herb with a woody rootstock. Stem decumbent, densely tomentose to villous, 7–15 cm tall, 0.3–0.5 mm in diameter at base; all leaves densely tomentose; basal leaves short petiolate, oblanceolate, 5–9 × 0.5–0.7 cm, apex acute, attenuate with a mucro, margins entire; median and upper leaves sessile, linear to lanceolate (median leaves 4–6 × 0.5–0.7; upper leaves 3–4.5 × 0.4–0.6 cm) with entire margins. Capitula solitary or rarely 2 at the end of branches, 37–47 × 12–17 mm (including flowers), ovoid and truncate at base, slightly narrowed towards apex. Phyllaries imbricate, pluriseriate, villous especially in upper part; outer phyllaries ovate, 7–10 × 3–5 mm; median phyllaries ovate to lanceolate, 13–18 × 5–6 mm; inner phyllaries linear to lanceolate, 24–27 × 3–5 mm; appendages triangular, not concealing basal part of phyllaries, not decurrent, entire in the outer and the median phyllaries with a spinule 2–3 mm long, irregularly lacerate in the inner phyllaries ending in a spinule 0.5–1.5 mm long. Florets yellow, marginal not radiant, ca. 35 mm long, corolla tube glabrous, 18–22 mm long, lobes 6–8 mm, linear with brown stripes along corolla. Mature achenes light brown, 6–6.5 × 3.5–4.5 mm, obovoid with striations, covered with adpressed whitish hairs; pappus simple, 18–22 mm, plumose, brownish. Flowering from June to July.

Etymology: —The species epithet is derived from Malatya Province, where the new species was first discovered.

Phenology: — Centaurea malatyensis flowers from June to July.

Conservation Status: —Following the criteria established by IUCN ( IUCN 2003), a provisional assessment of Critically Endangered (CR) (criteria B2a, B2biii) is proposed for this new taxon. It is endemic to East Anatolia (Malatya Province), and its area of occupancy (AOO) is less than 10 km 2 with the number of mature individuals being less than 50. In addition, the quality of the habitat is under serious threat because of goat grazing ( Bona & Asswad 2014).

Ecology: — Centaurea malatyensis grows on serpentine rocky slopes. It is endemic to East Anatolia and an Irano-Turanian element ( Fig. 3 ). The species grows together with Hypericum scabrum , Morina persica , Pelargonium endlicherianum , Salvia virgata , Marrubium globosum , Rosa canina , Papaver persicum , Marrubium astracanicum at altitudes between 1700–2000 m.

Achene surface morphology: —Achene surfaces of Centaurea malatyensis and C. leptophylla were studied by SEM. The achene surface pattern of C. malatyensis is undulate. Testa cells are irregularly arranged, elongated and parallel with the achene surface. Cell boundaries are relatively broad and raised above the cell centre. The achene surface pattern of C. leptophylla is glebulate. Testa cells are regularly arranged, elongated and parallel with the seed surface. Cell boundaries are thin, and the boundaries and cell centre are almost equal ( Fig. 4 ).

Discussion: — Centaurea malatyensis is a rare endemic of Central Turkey and is known only from the type locality which is positioned within the Southeastern extensions of the Taurus mountain range in Malatya Province. Centaurea malatyensis is similar to endemic C. leptophylla but clearly differs in some characters, such as the length of stem, indumentum, length of involucres, appendages and also the colour and shape of achenes. In addition, the new species differs from C. leptophylla in its habitat preference as the new species grows on stony slopes, whereas C. leptophylla grows on calcareous volcanic rocks. The most important diagnostic characters and comparison between these two species are given in Table 1.

Additional specimen examined (paratype):— TURKEY. Prov. Malatya: Doğanşehir, between Eskiköy and Asipınar, 1900 m, 17 July 2014, M. Bona (ISTE 102878).

Figures

FIGURE 1. Centaurea malatyensis. A. Habit, B. Leaves (a. basal; b. median; c. upper). C. Centaurea leptophylla, leaves (a. basal; b. median; c. upper).

FIGURE 2. A. Centaurea malatyensis, phyllaries (a–e) from the outher to inner; B. C. leptophylla, phyllaries (a–f) from the outher to inner; C. achenes; a. C. malatyensis, b. C. leptophylla.

FIGURE 3. Distribution map for ▲ Centaurea malatyensis and ♦ C. leptophylla in Turkey.

FIGURE 4. Scanning electron micrographs of achenes of Centaurea species. a–c. C. malatyensis, d–f. C. leptophylla.