Rosa tomurensis L. Luo, C. Yu & Q. X. Zhang

Deng, Tong, Luo, Le, Yu, Chao, Zhang, Qi-Xiang, Liu, Xue-Sen & Deng, Ze-Yi, 2022, Rosa tomurensis, a new species of Rosa (Rosaceae) from China, Phytotaxa 556 (2), pp. 169-177 : 174-175

Rosa tomurensis L. Luo, C. Yu & Q. X. Zhang ( Figures 3 , 4 , 5 )

Type: — CHINA. Xinjiang Uygur autonomous region, Akesu Prefecture, Wensu County, Tuomuerfeng Natural Preservation Areas , in river valleys, ca. 1800m, 10 June 2017, L. Luo, C. Yu, Y. J. Sui, F. Yang & S. Zhao 171022 (holotype BJFC00107674!) .

Diagnosis: — R. tomurensis is different from R. laxa in the following characteristics: prickles are rare, single prickles are larger, and the tip of prickles is not curved significantly; leaf blade apex serrate only, subbase one-third entire; flowers often solitary, and single flowers are larger than R. laxa ; receptacles purplish red, occasionally green; pedicels very long, purplish red or green; sepals are purplish red or green; hips are larger than R. laxa , often pendulous, hip apex without short neck; hip pedicels slightly inflated at base; sepals abaxially, receptacle and pedicel glandular or glandless together, the glands in the pedicel sometimes shed at anaphase. ( Table 2 ).

Description: —Shrubs, erect, 2.5–3 m tall, basal branching. Branchlets slender, brownish red; branchial spines are rare, scattered, rarely opposite, pale yellow and white, unequal in length, slender, broad at base, apex slightly downward curved. Leaflets 5–9, usually 7, elliptic, obovoid, ovoid or oblong, 0.6–2 × 0.5–1 cm, abaxially sparsely pilose, adaxially smooth; leaf margin simple serrate, often entire subbase one-third. Stipules usually wider, base mostly adnate to petiole, free portion ovate, triangulate, margin glandular spot. Flowers often solitary, sometimes 2–3 in corymbose cymes, (3) 3.5–6.5 (7) cm in diam; pedicel 1.5–3.5 cm, pedicel and calyx tube glabrous or tomentose and sparsely glandular hairs; bracts ovate, margin glandular teeth, abaxially with distinct midrib and lateral veins; sepals long lanceolate, margin entire, apex elongated widened into appendages, abaxially glandular and densely tomentose, adaxially densely pubescent, margin more densely; petals white, sparse pink,or pale pink, at bud stage, petal tips are often pink or pale pink. Hip subglobose or ovoid, red, shiny, 1–2.1cm in diam, 1.5–2 cm long, sepals persistent and spreading; fruit pedicel straight or bent.

Distribution and habitat: —This species is produced in the Tuomuerfeng Natural Preservation Areas of Wensu County in Aksu Perfecture, the Pamir Plateau Mountain Area of Kizilsu Kirgiz Autonomous Prefecture, Tajik Autonomous County of Taxkorgan in Kashgar Prefecture and the south slope of Duku Highway, Xinjiang Uygur Autonomous Region. It borns in arid mountains, river valleys and riparian thickets, at elevations between 1700 m and 3000 m. The associated woody plants in this area are R. laxa , R. albertii , Berberis sp. , Caragana sp. , etc.

Phenology: —Flowering from June to July, fruiting from August to October.

Etymology: —The specific epithet refers to the distribution where the new species was first discovered.

Paratypes: — CHINA. Xinjiang Uygur autonomous region, Akesu Prefecture, Wensu County, Tuomuerfeng Natural Preservation Areas , in river valleys, ca. 1800m, 24 September 2017, L. Luo, C. Yu, Y. J. Sui, F. Yang & S. Zhao 171023 (BJFC00107688!); the same locality, 8 June 2017, L. Luo, C. Yu, Y. J. Sui, F. Yang & S. Zhao 171024 (BJFC00107671!) .

Conservation status: —Based on currently available data, the species should be assigned to the ‘Data Deficient’ (DD) category of IUCN (2022). There is little human interference in this species’ distribution areas, so these populations are not easy to be destroyed.

Figures

FIGURE 3. R. tomurensis L. Luo, C. Yu & Q. X. Zhang, A. Plant, B. Flowers, C. Two types of buds, D. Floral anatomy, E. Stipule, F–G. Hip of two inflorescence forms.

FIGURE 4. Photographs of the types of Rosa tomurensis L. Luo, C. Yu & Q. X. Zhang, A. Holotype—BJFC00107674, B. Paratype— BJFC00107688.

FIGURE 5. R. tomurensis L. Luo, C. Yu & Q. X. Zhang, A. Habit, B–C. Leaf, D. Stipule, E. Prickle, F–H. Flower, I. Pink flower, J–K. Bud, L–N. Hip, O. Whole plant.