Parietaria semispeluncaria Yıldırım, 2015

Yildirim, Hasan, 2015, Parietaria semispeluncaria (Urticaceae), a new species from eastern Turkey, Phytotaxa 226 (3), pp. 281-287 : 283-286

Parietaria semispeluncaria Yıldırım sp. nov. ( Figs. 1–4 )

Diagnosis: Parietaria semispeluncaria most closely resembles P. rechingeri from which it differs in the pale brown coloured wood of the basal stems (as opposed to whitish coloured wood), younger stems with both densely pilose and short hooked hairs 0.6–0.9 mm (as opposed to sparsely adpressed-pilose hairs of 0.4–0.6 mm or subglabrous); the lower and upper leaf surfaces with densely pilose hairs (as opposed to indument of lower surface sparsely adpressed-pilose and the upper surface subglabrous); inflorescence composed of 3–9 flower clusters, each 2–3 mm in length (as opposed to 2–3 flower clusters, each 3–5 mm long), bracts 1.5–2.5 mm, broadly triangular to ovate with an acute apex, densely pilose (as opposed to 3–4 mm, broadly ovate with an obtuse to subacute apex, sparsely pilose); the perianth ca 2 mm, campanulate, dorsally pilose (as opposed to ca 3 mm in length, ellipsoid and dorsally adpressed-pilose); pistillate flowers narrowly ovate, pale yellow-green, the lobes narrowly linear lanceolate, the apex acuminate (as opposed to broadly ellipsoid, brown, the lobes broadly linear to lanceolate, the apex subacute); ovary narrowly ovate (as opposed to broadly ellipsoid).

Type: —Type: Turkey, Malatya: Akçadağ district, Levent Canyon, on marlstone cliffs, 38°23’31.03”N, 37°54’36.26”E, 1390 m, 16 June 2014, H. Yıldırım 2896 (holotype: EGE, isotypes: EGE, ANK, GAZI, NGBB).

Densely white pilose, dwarf suffruticose-caespitose perennial shrub, woody at the base, the wood pale brown in colour and fissured, 2–7 (–13) cm, caespitose with numerous erect stems. Stems terete, bearing two classes of hairs, densely soft, whitish straight and erect pilose, major hairs 0.6–0.9 mm, minor hairs hooked, to 0.2 mm. Leaves 5–18 × 3–12 mm, alternate, broadly ovate to elliptic, bearing two classes of hairs on lower and upper surfaces, hairs densely soft straight and erect pilose, major hairs 0.5–0.8 mm, minor hairs hooked, to 0.2 mm; lower surface pale green, upper surface dark green; primary veins 4–6, the basal pair ± opposite or alternate, the apical pair alternate; leaf base obtuse to cuneate, margin entire, apex obtuse to acute; petioles 3–6 mm, densely soft straight and erect pilose. Inflorescence cymose, axillary, usually present in all axils, occasionally restricted to upper axils, each axil includes two lateral clusters of flowers; clusters 2–3 mm, bearing 2 to 6 flowers, staminate flowers 1 or 2, pistillate flowers 1–5 per cluster; flowers sessile. Bracts 1.5–2.5 × 1.2–2 mm, broadly triangular to ovate, densely white pilose, acute, equalling and concealing the flower-clusters. Flowers unisexual. Staminate flowers 2–2.5 mm, perianth tube campanulate, divided for 1/2 to 2/3 of its length, pale yellow-green with mostly red veins on the outer surface of perianth lobes, whitish pilose; lobes narrowly lanceolate with acute to acuminate apex, pistillode present, yellow; stamens 4, filament ca 2 × 0.2 mm, anthers broad ovate, ca 1 × 1 mm. Pistillate flowers 2–2.5 × 0.4–0.5 mm, narrowly ellipsoid, pale yellow-green with red veins on outer surface, perianth segments divided for 1/6–1/7 of their length with red borders, linear lanceolate; ovary pale yellow, 1–1.5 × 0.6–0.8 mm, narrowly ovate; style slender, excluded, red; stigma discoid to circular, fimbriate, 1.5–2.5 × 1.5–2.5 mm, red. Mature achene shiny, ca 2 x 0.8 mm, narrowly ovoid, brown.

Etymology: —The specific epithet indicates that the plant grows just inside the entrance of large rock cavities.

Suggested Turkish name: “Mağara Sırçaotu”.

Distribution, Habitat and Ecology: — Parietaria semispeluncaria is a local endemic restricted to the Levent Canyon in Malatya, eastern Anatolia. It is an element belonging to the Irano-Turanian floristic region and colonizes only marlstone-calcareous cliffs, usually those with an eastern orientation, at an elevation of 1220–1400 m ( Fig. 3 ). It is an obligate chasmophyte.

Species conservation assessment: —The population area of Parietaria semispeluncaria was calculated as 0.265 km 2 with ca. 650 individuals observed. Following IUCN (2012) criteria the plant is categorized as ‘Vulnerable’ (VU) based on criteria D1 + 2, restricted distribution. No anthropogenic or grazing effects were observed on the population. Levent Canyon is under legal protection of the governorship of Malatya Province. For this reason, it is not expected to be under threat of extinction in the near future.

Figures

FIGURE 1. Parietaria semispeluncaria:A. habit, C1. upper surface of leaf, C2. lower surface of leaf, E. stem surface, G. pstillate flower, I. perianth segment of pistillate flower, K. staminate flower, M. ovary, O1–O4. bracts; Parietaria rechingeri:B. habit, D1.upper surface of leaf, D2.lower surface of leaf, F. stem surface,H. pistillate flower, J. perianth segment of pistillate flower, L. staminate flower, N. ovary, P1-P2. bracts.

FIGURE 2. Parietaria semispeluncaria:A. habit, B. flower cluster with pistillate flowers, C. flower cluster with staminate flowers.

FIGURE 3. Parietaria semispeluncaria: A. population, B. habits, C. habit with flower clusters, D. habit with fruting time clusters, E. leaf, F. habit with staminate flower buds, G. fruit

FIGURE 4.SEM photographs of Parietaria semispeluncaria: A–D. pollen grain and pollen surface, E. infructescence, F.fruit.