Arenaria izmirensis Eroğlu sp. nov. (Figs. 1,2,4)

Type: — TURKEY (B1 İzmir): Kemalpaşa, Mahmut Mt., phyllite rocks, Pinus nigra forest, 1180 m, 38°20´21ʺN, 27°30´21ʺE, 14 June 2020, Eroğlu s.n. (holotype EGE43734!, isotype IZ0101!).

Diagnosis: — Arenaria izmirensis differs from A. tmolea, A. uninervia, A. cretica, and A. sipylea by its procumbent habit, densely glandular-pubescent to densely-pubescent stem hairs, leaves elliptic (4–8 × 1.5–2.5 mm), densely pubescent (cauline leaves) or orbicular to elliptic, glabrous (blade) (basal leaves), sepals densely glandular and 3.4–4.4 × 1.2–1.3 mm petal size (see Table 1).

Description: —Procumbent perennial herb, densely glandular-pubescent hairy except basal leaves. Stems erect or ascending, 4–14 cm long and 0.5–1.0 mm in diameter, from above to base, densely glandular-pubescent to densely pubescent, fragile, single or branched from base. Leaves dimorphic. Stem leaves elliptic, 4–8 × 1.5–2.5 mm, densely pubescent, sessile or petiolate 0.12–0.15 mm, apex acuminate, base cuneate, margins entire and without long hairs. Basal leaves orbicular to elliptic, 3.5–7.0 mm × 1.2–3.5 mm, glabrous or ciliate at base, petiolate, apex acuminate, base orbicular to cuneate. margins entire and without long hairs. Bracts lanceolate, 2.0–2.5 × 0.5–0.8 mm, apex acuminate. Pedicel 5–10 mm, erect, dense, very thin. Inflorescence terminal and lateral by development of an axillary branch, lax clusters; flowers pedicellate, per cyme 5–22-flowered. Sepals ovate, 3.00 × 0.15 mm, with a distinct mid-vein and obscure lateral veins; apex acuminate, scarcely carinate. Petals ±oblanceolate, 3.8–4.4 × 1.2–1.3 mm, Petals 1.5 mm long as or as long as sepal ±, white; apex obtuse to truncate; cuneate at the base; persistent at maturity. Stamens 10; filaments 1-2 mm, not exceeding corolla. Styles 0.8–1.2 mm. Capsule subglobose, 1.5–2.0 × 1.0– 1.5 mm, 5–14- seeded, shorter than sepals.

Seed micromorphology: —Seeds reniform, 0.54 × 0.36 mm, blackish or brown; lateral surfaces papillate, dorsal surfaces higher papillate; cells irregular, polygonal, margins entire; anticlinal cell walls uncertain V-undulate; periclinal cell walls convex, wrinkled.

Pollen micromorphology: —Pollen unit: monad, dispersal unit and peculiarities: monad, size (pollen unit): medium-sized (24–26 µm), pollen class: porate, shape: spheroidal, outline in polar view: circular, shape (dry pollen): polygonal, outline in polar view (dry pollen): polygonal, aperture number 12, aperture type: porus, aperture condition: porate, pantoporate, aperture peculiarities: aperture membrane ornamented, pantoaperturate, ornamentation SEM: perforate, microechinate, Ubisch bodies: present.

Etymology: —The specific epithet is derived from İzmir Province, where Arenaria izmirensis was discovered.

Phenology: —Flowering time from May to June; fruiting time from June to July.

Ecology and distribution: — Arenaria izmirensis is a local endemic restricted to Mahmut Mountain in Bozdağ Mountain chain in İzmir, Western Anatolia (Fig. 3). Excepting for the summit of Mahmut Mountain, the rock structure is densely schist. There is a phyllite rock structure at the summit and parts close to the summit. These rocks provide an isolated area from the surrounding area. Campanula mugeana Yıdirim (2013: 419), which is the local endemics of Mahmut Mountain, have spread only in this isolated region (Yıldırım 2013). Also A. izmirensis has only distribution on this region and it is geographically, ecologically and morphologically isolated from other species. The new species colonizes screes between 1180 and 1250 m. a.s.l. Other species that share the same rock are; Asplenium septentrionale (Linnaeus 1753: 1068) Hoffman (1795: 12), Valantia hispida Linnaeus (1759: 1307), Catapodium rigidum (Linneaus 1755: 5) Hubbard (1953: 437). subsp. rigidum and Poa bulbosa Linnaeus (1753: 70)

Taxonomical notes: —According to McNeill (1962), Arenaria subg. Arenaria would be divided into 10 sections. A. izmirensis belongs to sect. Rariflorae Williams (1895: 602).

Conservation status: — Arenaria izmirensis is currently known only for locus classicus (Mahmut Mountain of Izmir). 120 individuals were counted and they occupy an area of about 80 m 2. The site is under risk of road widening caused by wind power plant. This population should be assessed as CE-Critically Endangered according to the criteria CR-B1ab(iii,iv), C1, and D of IUCN (2022).