Hesperis sivasica Özüdoğru, Altınözlü & Özgişi, 2024

Özüdoğru, Bariş, Altinözlü, H. & Özgişi, Kurtuluş, 2024, Hesperis sivasica (Brassicaceae), A new crucifer species from inner Anatolia, Phytotaxa 649 (3), pp. 261-269 : 262-267

Hesperis sivasica Özüdoğru, Altınözlü & Özgişi sp. nov. ( Figure 2 – 4 )

Type: — Türkiye, Sivas: 3 km west of Kangal , marly soil, 1610 m, 39. 231150 N, 37.355660 E, 16.06.2023, B. Özüdoğru 6060, K. Özgişi & H. Gür (holotype HUB!; isotypes ANK!, HBH!) .

Diagnosis: —There is no close morphological relatives of H. sivasica in the genus Hesperis . However, it is similar to H. kotschyi in its trichomes, also close to H. bottae and H. thyrsoidea phylogenetically, but easily distinguished from them by having short pedicels, flowers, short and compressed-terete fruits.everal characters presented in Table 1 .

Description: —Rhizomatous perennial with creeping underground stems. Most part of the plant (leaves, pedicels, sepals, fruits) canescent with many-rayed dendritic trichomes with an admixture of rare stalked glandular hairs on leaves. Aboveground stems prostrate to ascending, 10–20 cm tall (including flowering part), solitary or tufted (2–5 stems), terete, ± smooth or slightly sulcate; densely to moderately pubescent with dendritic trichomes. Leaves crowded at base; basal leaves erect-ascending, spathulate or oblanceolate, sinuate or remotely dentate, obtuse, 3–4(–4.5) × 0.3– 0.8 cm (including petiole 1.5–2.8 cm), densely covered by dendritic hairs with very few glandular hairs; cauline leaves few, 1–3, oblong-elliptic (5–)10–18(–20) × 2–5 mm, lyrate, oblong-elliptic, entire or ± remotely dentate, obtuse to acute, sessile or rarely very short petiolate, attenuated at the base, covered by dendritic trichomes with sparse glandular hairs. Inflorescence raceme. All flowers ebracteate. Pedicels ascending to erect, 1–2.5 mm long at anthesis, up to 6 mm at fruit, trichomes dendritic. Sepals pale pinkish with white membranous margin, oblong, deciduous, 3.1–3.3 × 1.2–1.3 mm, inner sepals saccate, trichomes dendritic, 0.17–0.5 mm long. Petals narrowly obovate to oblong, 6.5–7.3 × 1.5–1.6 mm, pale pink with distinct vines, obtuse or rounded. Outer filaments 1.9–2.0 mm long, dilated at base, inner filament 2.6–2.7 mm long, glabrous. Anthers all fertile, ± linear, 1.1–1.2 × 0.3–0.4 mm, yellowish. Stigma with 2 obtuse, decurrent carpidial lobes. Ovary tomentose with dendritic hairs. Siliquae 10–25 × 2.1–2.3 mm, compressed-terete, dehiscent, slightly torulose, straight, ascending to erect, grey to brownish. Seeds 1–4 in each loculus, yellowish to light brown, 2.9–3.4 × 1.1–1.4 mm.

Phenology: — Hesperis sivasic a has been found flowering in May – June, and fruiting in June – July.

Eponymy and suggested Turkish name: —Since this species only occurs in the province of Sivas, Türkiye, it has been named Hesperis sivasica . The Turkish name of this species is given as “ Sivas Yıldızı” according to the guidelines of Menemen et al. (2013).

Distribution and habitat: —The species is known only from the type locality where it grows on marly plains at about 1600 m a.s.l., about 3 km west of Kangal district, Sivas, Türkiye ( Fig. 5 ).

Conservation status: — Hesperis sivasica is a local endemic restricted to the part of a marly area of Kangal District (Sivas, Türkiye) ( Fig. 5 ). The occupancy area (AOO) of new species was calculated as ca. 1 km 2 in which about <100 mature individuals were estimated to occur. In view of the overgrazing pressure on the plant's habitat, its proximity to the settlement centre and the existence of only one population, the threat category of this species is recommended as CR B1ab(i, ii, iii) + 2ab(i, ii, iii) + C2a(ii) according to the IUCN Red List Criteria (IUCN 2020).

Trichome micromorphology: — Hesperis sivasica has an indumentum consisting entirely of dendritic hairs ( Fig. 3 ). Trichomes are less abundant on the stem than on the leaves and fruit. All dendritic hairs on the plant have cuticular warts. Glandular hairs are very sparse and are usually found on leaves ( Fig. 3c–d ).

Figures

FIGURE 2. General view of Hesperis sivasica. A) Habitus, B) Basal leaves, C) Flower, D) Fruits, E) Rhizomes, F) Habitat.

FIGURE 3. SEM (Scanning electron microscopy) micrographs of the stem, leaf, pedicel, and fruit of Hesperis sivasica. A) Stem, B) Stem leaf, C–D) Basal leaf (d=dendritic hair, g= stalked gland, sc= stalk cell, hc= head cell), E) Pedicel, D) Fruit.

FIGURE 4. Fruit with septum and seeds of H. sivasica. A) Fruit, B) Seeds. Bars=1 mm.

FIGURE 5. Distribution map of H. sivasica (red circle), H. kotschyi (blue circle), H. bottae (orange circle), and H. thyrsoidea (green circle). The highlighted green area shows the Anatolian Diagonal.