Clematis mae Z.Z. Yang & L. Xie, 2019

He, Jian, Lyu, Ru-Dan, Yao, Min, Xie, Lei & Yang, Zong-Zong, 2019, Clematis mae (Ranunculaceae), a new species of C. sect. Meclatis from Xinjiang, China, PhytoKeys 117, pp. 133-142 : 135-138

Clematis mae Z.Z. Yang & L. Xie sp. nov. Figs 1 , 2 , 3 A–C

Diagnosis.

The new species is most similar to C. orientalis L. and C. glauca Willd. and it can be distinguished from the latter two species by the following combinations of characteristics. Plants of the new species are less hairy than C. orientalis and, in this respect, are similar to C. glauca . The leaves of the new species are often 2-ternate, with lanceolate to linear lanceolate leaflets. Its leaflets are larger than those of C. orientalis , but narrower than those of C. glauca . The flowers are also significantly larger than those of C. orientalis and slightly larger than those of C. glauca . The sepals of the new species are also less hairy than those of C. orientalis and similar to those of C. glauca . The shape of the sepal is lanceolate and the apex is acute to slightly attenuate. In C. orientalis , the sepals are often linear, oblong and reflexed. The sepals of C. glauca are often wider than those of the new species (Table 1 , Fig. 3 ).

Type.

CHINA. Xinjiang: Toksun, Yuer gou, alt. 2590 m, sandy bank along the river, 22 Aug. 2018, fl, fr, M. Ma & Z.Z. Yang 99348 (holotype: BJFC; isotypes: 3 ex BJFC).

Description.

Woody vine. Branches slender, shallowly 6 sulcate, very sparsely puberulous. Leaves pinnate to 2-ternate, very rarely ternate, up to 16 cm in length and 13 cm in width; living leaflets dry, green or sometimes grey-green, papyraceous to chartaceous, lanceolate to linear-lanceolate, 1.8-6.5 × 0.3-0.8 cm, glabrous on the upper side, sparsely puberulous on the lower side, usually 2-3-lobed to 2-3-sect, sometimes undivided, terminal lobe lanceolate to linear-lanceolate, 0.4-0.8 cm broad, margin entire, never dentate, midrib adaxially flat or slightly prominent, abaxially clearly prominent. Cymes all axillary, (1 –2–)3– flowered; peduncles 2.5-3.0 cm long, slender; bracts petiolate, leaflet-like, up to 3.5 cm long; central flower of the 3 flowered cyme without bracteole, two lateral flowers bracteolate; bracteole petiolate and leaflet-like, up to 8 mm long. Flower 3.8-5.8 cm diam.; pedicel 2.8-5.2 cm long, puberulous, upper pedicel usually densely hairy. Sepals 4, pinkish-purple outside and yellow inside, ascending, lanceolate, 18-27 × 4-6.5 mm, puberulous on both surfaces, outside margin velutinous, apex acute to slightly attenuate. Stamens more than 30, 9-12 mm long; filaments lanceolate linear, widened in the lower part, pubescent; anthers linear to narrowly oblong, 3-4 mm long, glabrous, apex obtuse, minutely apiculate. Carpels numerous, up to 60 per flower; ovaries pubescent; styles 8-12 mm long, densely villous. Achenes laterally compressed, elliptic, ca. 3.9 × 2.1 mm, puberulous; persistent styles 6.5 cm long, plumose.

Specimens seen (paratypes).

CHINA. Xinjiang: Toksun, Yuer gou, alt. 2600 m, 22 Aug. 2018 (fl, fr), M. Ma & Z.Z. Yang 99349, 99355 (paratypes: BJFC).

Phenology.

Flowering and fruiting time: July to September.

Distribution.

Only known from its type locality, Yuer gou, Toksun, Xinjiang, China.

Vernacular name.

Ming Tie Xian Lian (明铁线莲; new Chinese name)

Habitat and conservation status.

According to currently available data regarding C. mae , it occurs only in its type locality. The environment of the habitat is stable. We found about 200 individuals of the new species scattered along the river bank (elevation ca. 2500-2600 m) of Yuer Gou, Toksun Co. and we did not find individuals of this species outside this area. The herbarium investigation showed that several C. sect. Meclatis specimens were collected in Toksun Co., e.g. AJ Li & JN Zhu 7288, 7335 (PE) and QR Wang et al. 4209 (PE); however, these specimens were collected at least 70 km from Yuer Gou and morphologically belong to C. orientalis . Based on currently available data, we considered the new species to be a local species endemic to a small area of Yuer Gou, Toksun Co. The open areas of the riverside, in which the new species occurs, may be threatened by settlements and agricultural activities. Therefore, we propose that the new species should be treated as Endangered (EN) in the International Union for Conservation of Nature (IUCN) categories system ( IUCN 2012).

Etymology.

The species epithet is chosen in honour of the collector, Ms. Ma Ming, who first noticed this new species and guided the last author to collect specimens.

Taxonomic notes.

The new species clearly belongs to sect. Meclatis by its ascending sepals and pubescent and linear-lanceolate stamen filaments ( Tamura 1995, Wang 2006) and is more similar to C. glauca than to C. orientalis . Observations of hairs, leaflets, flower size and shape and other characteristics clearly demonstrate that the new species is a taxonomic entity distinct from C. orientalis . Clematis orientalis is one of the most widely distributed species in its genus and has a wide range of morphological variation ( Grey-Wilson 1989, Brandenburg 2000, Wang 2006). Both Grey-Wilson (1989) and Wang (2006) recognised seven varieties. The leaf shape of C. orientalis is strikingly variable (summarised by Grey-Wilson 1989) and may be similar to that of C. mae , but the leaves of C. mae are thinner than those of C. orientalis . Moreover, C. orientalis is often identified by its grey leaves, hairy stems and flowers and reflexed linear-oblong sepals. Clematis mae from central Xinjiang is less hairy than C. orientalis and has larger flowers with ascending lanceolate sepals (Fig. 3 ). The hair and floral characteristics of the new species are somewhat similar to those of C. glauca , another widely distributed species with wider leaflets and sepals. In comparison with C. orientalis , C. glauca has less hairy stems and flowers, much wider leaflets and sepals and non-reflexed sepals. The primary differences between the new species and C. glauca are their leaflet shape, sepal shape and flower shape and size. Furthermore, the bracteoles of C. glauca are sometimes 3-lobed, which is never the case in C. mae .

Additional specimen examined

Clematis orientalis L., Sp. Pl. 1: 543. 1753.

AFGHANISTAN. Kokcha-Tal, D. Podlech 12732 (E).AZERBAIJAN. Caucasus, Kolakovsky 1413 (MW). CHINA. Inner Mongolia, Ejina, ZY Zhu & DS Wen 013 (HIMC); Gansu, Minqin, YQ He 3332 (PE, WUK); Gansu, Jiuquan, Qinghai-Gansu Exped. 2968 (PE), ZJ Dong 270 (WUK). Xinjiang, Altay Shan, RC Ching 2813 (PE); Xinjiang, Aqtau, YC Wang Y172, Y180 (BJFC); Xinjiang, Gongliu, Xinjiang Exped. Inst. Northwest Bot. 2667 (PE); Xinjiang, Hami, RC Ching 122 (PE); Xinjiang, Hejing, Baluntai, TY Zhou et al. 651335 (NAS), T Zhang et al. 0443 (KUN); Xinjiang, Hetian, Kelimu 106 (XJBI); Xinjiang, Korla, AJ Li & JN Zhu 8641 (PE); Xinjiang, Qira, Xinjiang Exped. 56-129 (PE); Xinjiang, Kunlun Shan, ZQ Xie 25 (XJA); Xinjiang, Shanshan, AJ Li & JN Zhu 6692 (PE); Xinjiang, Shihezi, ZZ Yang 0857, 0858 (BJFC); Xinjiang, Tian Shan, TN Liou 2689 (PE); Xinjiang, Toksun, AJ Li & J N Zhu 7288 (PE), QR Wang et al., 4290 (PE); Xinjiang, Turpan, ZM Zhang 294 (PE); Xinjiang, Ürümqi, TN Liou 2891 (PE); Xinjiang, Yecheng, Qinghai-Xizang Exped. 87-764 (PE), Xinjiang, Kashi, Abulimit 258 (XJA); Xinjiang, Zhaosu, Xinjiang Exped. Inst. Northwest Bot. 2593 (PE). IRAN. Khorasan, Koelz 16822 (US). KAZAKHSTAN. Dzhambul, Raikova 2915 (PE); Western Tianshan, Mekerov 400 (PE); Issyk, A. Regel 498 (K).MONGOLIA. South-western Mongolia, Огуреева s.n. (MW). RUSSIA. Dagestan, Куликова s.n. (MW). TURKEY. Tortum, Davis 47565 (K); Oltu valley, JC Archibald 8281 (E).TURKMENISTAN. Aschabad, P. Sintenis 1055 (E). UZBEKISTAN. Taskent, Ellas, Murray & Newcomba 9873 (PE) . Clematis glauca Willd., Berl. Baumz. 65. t. 4, fig. 1. 1796.

CHINA. Gansu, Liancheng, J He & L Xie 2018GS009 (BJFC), RF Huang 2111 (HNWP); Gansu, Tianzhu, RF Huang 2601 (HNWP). Qinghai, Qilian, collector unknown 8532 (HNWP); Qinghai, Huzhu, BZ Guo 25547 (HNWP). Xinjiang, Altay Shan, RC Ching 2332 (PE); Xinjiang, Burqin, YR Ling 74-1008 (PE); Xinjiang, Ili, XY Li YL 96015 (XJBI); Xinjiang, Gongliu, YC Wang Y171 (BJFC); Xinjiang, Korla, AJ Li & J N Zhu 8642 (XJBI); Xinjiang, Ulastai, KC Kuan 3816 (PE); Xinjiang, Wenquan, Hoch & J. R. Chen 86-308 (PE). Xinjiang, Ürümqi, RC Ching 628 (PE). RUSSIA. Altai Mountain, Chuya River, Elias, Weber, Tomb & Krasnoborov 4411 (PE).

Key to the species of Clematis sect. Meclatis

Figures

Figure 1. Holotype specimen (M. Ma & Z. Z. Yang 99348, deposited in BJFC) of the new species, Clematis mae Z. Z. Yang & L. Xie, collected from Yuer gou, Toksun, Xinjiang, China.

Figure 2. Illustration of Clematis mae Z. Z. Yang & L. Xie. Drawn by S. F. Li

Figure 3. Field photographs of three closely related species of sect. Meclatis. A-C Clematis mae Z. Z. Yang & L. Xie. (photo taken by M. Ma & Z. Z. Yang) A Biternate leaf and flower buds B Ascending flower and its outside sepals C Flower inside D-F Clematis orientalis L. (photo taken at Shihezi, Xinjiang, China, by Z. Z. Yang) D Habitat and plants of C. orientalis E Flower showing spreading and reflexed sepals F Flower showing discernible hair on the inside sepals G-I Clematis glauca Willd. (photo taken at Liancheng, Gansu, China, by J. He and L. Xie) G Habitat and plant in flower H Cyme and leaves I Flower and young fruit.