Thalictrum ramosum Boivin (1945: 115)

Zeng, You-Pai, Yuan, Qiong & Yang, Qin-Er, 2023, Thalictrum minutiflorum (Ranunculaceae), described from Guizhou province, China, is merged with T. ramosum, Phytotaxa 609 (3), pp. 165-179 : 166-177

Thalictrum ramosum Boivin (1945: 115) . Figs. 1‒11

Type:— CHINA. Sichuan: South of Kuan Hsien (= Guanxian, now Dujiangyan), ditch side, alt. 850‒950 m, 14 April 1930, F.T. Wang 20378 (holotype GH00038613!; isotypes KUN0690510!, NAS00070708!, PE00028263!, PE00028264!, PE00028265!, WUK (herb. no. 329920)!). Figs. 2 , 3 .

= T. minutiflorum Wang (2017: 407) , syn. nov.

Type:— CHINA. Guizhou: Dejiang, Tongjing town , Gaojing village , in sparse forest, alt. 600 m, 26 March 2003, M.X. An 3048 (holotype PE00875647!). Fig. 1 .

Description:—Perennial herbs. Roots fibrous. Stems 12‒50 cm tall, basally branched, sometimes initially very sparsely pubescent, later glabrescent. Leaves 2‒4-ternate; blade triangular, 7‒15 cm long, 5‒14 cm broad; leaflets ovate, broadly ovate, obovate, cuneate-obovate, obliquely ovate or suborbicular, 0.3‒4 cm long, 0.5‒4 cm broad, herbaceous, both sides glabrous, green on adaxial side, pale green on abaxial side, base rounded or subcordate, apex obtuse or acute, 3-lobate; lobes crenate-dentate; veins flat adaxially, raised abaxially; petiole slender, 2‒10 cm long; stipule membranous, margin torn. Inflorescence a compound cyme, corymbiform. Pedicels 5‒10 mm long, initially sometimes very sparsely pubescent, later glabrescent. Flowers bisexual, erect. Sepals 4, caducous, elliptic or broadly ovate, 2‒2.5 mm long, 1.6‒2 mm broad, greenish white or tinged with purplish, glabrous. Stamens 16‒24, 3‒4 mm long; filaments narrowly clavate, 2.5‒3 mm long, whitish or purplish; anthers oblong, 0.7‒1 mm long, apex obtuse, whitish. Carpels 6‒16, sessile, 1.5‒2.2 mm long; ovary lunate-fusiform, shallowly ribbed, ca. 1 mm long, glabrous; style ca. 1 mm long, straight or slightly recurved at apex; stigma inconspicuous, lanceolate, ca. 0.5 mm long. Achenes sessile, 4‒5 mm long; body fusiform, profoundly ribbed; style persistent, recurved at apex.

Phenology:—Flowering from March to May; fruiting from April to June.

Distribution and habitat:— Thalictrum ramosum is widely distributed in Chongqing, northwestern Guangxi, Guizhou, western Hubei, western Hunan, central and southwestern Sichuan, and northeastern Yunnan, China ( Fig. 12 ). It grows along stream sides or in shady moist places in bamboo forests or scrubs at elevations of 150‒1200 m above sea level.

Additional specimens examined:— CHINA. Chongqing: Ba’nan, T.T. Yu 2855 (IBSC, PE); Beibei, Anonymous 1290 (NAS), S.S. Chien 6001 (NAS), C. Ho & T.L. Chow 977 (SZ), Z.M. Huang 1217 (JJF, SM), Y.W. Law 535 (IBSC, K, NAS), C. Pei 7048 (NAS), R.H. Shan 1175 (NAS), S.C. Wang 1468 (NAS, PE), C.W. Yao 3473 (KUN, NAS); Dianjiang, Dianjiang Tra. Chin. Med. Exped. 49 (SM); Fuling, Fuling Exped. 178 (SM); Hechuan, Hechuang Exped. 656 (SM); Jiangjin, Jiangjin Group 88 (SM); Nanchuan, Z.Y. Liou et al. 183805 (IMC); Pengshui, S.X. Tan et al. 288 (IMC, SM); Qianjiang, Anonymous 51 (SM), S.X. Tan et al. 890 (IMC); Rongchang, Rongchang Exped. 561 (SM); Shizhu, Anonymous 451 (SM), Shizhu Exped. 38 (SM); Wanzhou, IBCAS Three Gorg. Exped. 741 (PE). Guangxi: Fengshan, W.Y. Huang 30452 (PE). Guizhou: Chishui, G.P. Li 87-69 (GZTM), M.C. Wang 520381160604861LY (GZTM); Daozhen, Z.Y. Liu 2035759 (IMC); Dejiang, C.M. Wang 158 (GZTM); Guiyang, Wudang Exped. 520112140527028LY (GZTM); Huichuan, Y.M. Wang 87-280 (GZTM); Jiangkou, T.S. Chang et al. 400061 (HGAS, PE), Y.P. Zeng & J.R. Chen 36 (IBSC), Y.P. Zeng & J.R. Chen 40 (IBSC); Taijiang, Y.F. Shi 405 (GYBG); Xifeng, T.H. Yang 634 (GZTM); Yuping, J. Zhou 522223140621008LY (GZTM); Zheng’an, A.Y. Lu et al. 482 (GZTM); Zunyi, P.F. Zhang 522121160331023LY (GZTM). Hubei: Yichang, A. Henry 1235 (E, P), Z.D. Jiang & G.F. Tao 21 (E), Z. Zheng 2 (PE). Hunan: Cili, G.X. Zhu 2 (NAS); Hongjiang, Hunan Anjiang Agr. Coll. Group 5 (IBSC, PE), Z.T. Li 1748 (IBSC, PE); Longshan, D.K. Tian et al. LS1145 (CSH); Longhui, Anonymous s.n. (PE); Xinning, L.B. Luo 502 (PE). Sichuan: Chengdu, S.S. Chien 5880 (E, GH, SZ), W.P. Fang 12051 (BM, HGAS, IBSC), W.P. Fang 13264 (KUN, NAS, SZ), W.P. Fang 19855 (SZ), W.P. Fang 20133 (SZ), W.K. Hu 7691 (E, SZ), W.K. Hu 7775 (E, SZ); Chongzhou, Anonymous 58 (SM); Dazhou, Daxian Exped. 18 (SM); Dazhu, Anonymous 286 (SM), Anonymous 315 (SM); Dujiangyan, D.Z. Fu 87-0415 (WCSBG), D.Z. Fu et al. 87-0422 (WCSBG), X.J. He & Q.S. Zhao 152833 (SZ), X.J. He & Q.S. Zhao 155423 (SZ), X.J. He & Q.S. Zhao 155822 (SZ), X.J. He & Q.S. Zhao 156333 (SZ), X.J. He & Q.S. Zhao 156461 (SZ), X.J. He & Q.S. Zhao 156819 (SZ), C. Ho 12194 (IBSC, SZ), H.W. Limpricht 1236 (K); Ebian, Ebian Group 147 (SM); Emei Shan, S.Y. Chen et al. 3027 (NAS, SM), W.C. Cheng 10095 (KUN, SZ), W.C. Cheng 10242 (KUN), S.S. Chien 5424 (SZ), C.L. Chow 5526 (SZ), Emeishan Exped. 18 (SM), W.P. Fang 13939 (KUN, NAS, SZ), W.P. Fang 13974 (IBSC, KUN, NAS, PE, SZ), W.P. Fang 14023 (SZ), W.P. Fang 14084 (KUN, NAS, PE, SZ, TIE), W.P. Fang 15960 (IBSC, PE, SZ), X.R. Jiang 165 (PE), C.H. Li 97-344 (PE), S.L. Sun 14 (KUN, NAS, SZ, TIE), S.G. Tang 7815 (SM), Y.X. Xiao 48001 (SZ), H.G. Xu 130 (PE), H.G. Xu 2418 (PE), T.T. Yu 274 (GH, NAS, PE), Z.S. Zheng 367 (KUN); Guang’an, S.Y. Chen 2021 (SM); Hongya, Anonymous 72-30 (SM); Leshan, H.C. Chow 9426 (NAS), L.Y. Tai 771 (NAS), L.Y. Tai 1742 (NAS), L.Y. Tai 1745 (NAS), T.T. Yu 203 (PE); Leibo, X.J. He & Q.S. Zhao 198620 (SZ); Linshui, Anonymous 317 (SM); Lushan, Lushan Exped. 78-0002 (SM); Mingshan, Mingshan Exped. 23 (SM); Pengshan, Anonymous 637 (SM); Pingshan, Sichuan Econ. Plant Exped. 784 (KUN, PE); Qingshen, Sichuan Econ. Plant Exped. 5070 (KUN); Qionglai, Anonymous 142 (SM); Quxian, Anonymous 61 (SM); Shifang, Anonymous 10 (SM), Anonymous 11 (SM); Tianquan, D.Y. Peng 45102 (CDBI, IBSC); Xuanhan, Xuanhan Exped. 236 (SM); Ya’an, X.J. He & Q.S. Zhao 160681 (SZ), C.C. Hsieh 39528 (NAS, PE, SZ, WUK), Ya’an Exped. 197 (SM); Yuechi, S.Y. Chen 154 (SM). Yunnan: Daguan, E.E. Maire s.n. (P); Shuifu, Z.Y. Liu 2020319 (IMC).

Notes:— Lecoyer (1885) mentioned the name Thalictrum minutiflorum Meyer , but this name has never been validly published. According to Art. 6.3 and Art. 12.1 of the International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) ( Turland et al. 2018), a name not validly published has no status in nomenclature. Therefore, the name T. minutiflorum Wang is legitimate, and not a later illegitimate homonym.

Of the collections cited under Thalictrum ramosum by Wang (2018), the collection information of some of the specimens was erroneous and some specimens were misidentified. The collection C.C. Hsieh 39528 is actually made from Ya’an, not Shimian, in Sichuan; the collection H.G. Xu 180 from Emei Shan in Sichuan should be corrected as H.G. Xu 130; the collection Z.T. Li 1738 from Xuefeng Shan in Hongjiang, Hunan, should be corrected as Z.T. Li 1748; the collection T.S. Chang 40006 from Jiangkou in Guizhou should be corrected as T.S. Chang 400061. The collections Bailongjiang Exped. 1311 from Zhugqu and Baishuijiang Exped. 2286 from Wenxian, both in Gansu, and Sichuan Plant Exped. 8599 from Maoxian in Sichuan, should all belong to T. pseudoramosum Zeng et al. (2021a: 134) ; the collection Z.C. Zhao 2736 from Shimian in Sichuan should belong to T. bouffordii Zeng et al. (2021c: 18) ; the collections Bashan Exped. 5550 and Bashan Exped. 5625 both from Nanjiang in Sichuan should belong to T. fargesii Franchet ex Finet & Gagnepain (1903: 608) . Li (2014a, b), misled by the misidentification of the collections Baishuijiang Exped. 2286, Bashan Exped. 5550 and Bashan Exped. 5625 just mentioned above, wrongly recorded the occurrence of T. ramosum in Gansu.

Figures

FIGURE 1. Holotype sheet of Thalictrum minutiflorum (= T. ramosum). Inset a: flowers, with sepals having fallen off; inset b: aggregate fruits.

FIGURE 2. Holotype sheet of Thalictrum ramosum. Inset a: flowers, with sepals having fallen off; inset b: aggregate fruits.

FIGURE 3. Isotype sheets of Thalictrum ramosum. A. Inset: aggregate fruit (immature). B. Inset: aggregate fruits (immature). C. Inset: flower, with sepals having fallen off. D. Inset a: flower, with sepals having fallen off; inset b: aggregate fruits (immature).

FIGURE 4. Paratype sheets of Thalictrum ramosum. A. China, Sichuan, Chengdu, S.S. Chien 5880 (E). B. Duplicate (SZ); inset: flower, with sepals having fallen off. C. China, Sichuan, Emei Shan, T.T. Yu 274 (NAS); inset: aggregate fruit (immature). D. Duplicate (PE); inset: aggregate fruits (immature).

FIGURE 5. Selected specimens (A, B: Dujiangyan in Sichuan, the type locality; C, D: Emei Shan in Sichuan, the paratype locality) of Thalictrum ramosum, showing the variation in size of leaflets within a population. A. D.Z. Fu 87-0415 (WCSBG). B. D.Z. Fu et al. 87- 0422 (WCSBG). C. S.L. Sun 14 (KUN). D. H.G. Xu 2418 (PE).

FIGURE 6. Selected specimens of Thalictrum ramosum, showing the variation in number of stamens between populations. A. China, Sichuan, Ya’an, C.C. Hsieh 39528 (PE); inset: flower, with sepals having fallen off. B. China, Chongqing, Beibei, S.C. Wang 1468 (NAS); inset: flower, with sepals having fallen off. C. China, Sichuan, Banan, T.T. Yu 2855 (PE); inset: flower, with sepals having fallen off. D. China, Chongqing, Beibei, C.W. Yao 3473 (NAS); inset: flower, with sepals having fallen off.

FIGURE 7. Thalictrum ramosum in the wild (Chengdu in Sichuan, China, the paratype locality).A. Habit. B. Portion of inflorescence. C. Leaves. D. Leaflets. E. Portion of inflorescence rachis and pedicel. F. Flower, with sepals having fallen off. G. Carpels. H.Aggregate fruit (immature). I. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 8. Thalictrum ramosum in the wild (Emei Shan in Sichuan, China, the paratype locality).A. Habit. B. Portion of leaf. C. Portion of inflorescence. Photographed by K. Zhang.

FIGURE 9. Thalictrum ramosum in the wild (Jiangkou in Guizhou, China). A. Habitat. B. Habit. C. Roots. D. Portion of stem. E. Portion of leaf (left: adaxial side; right: abaxial side). F. Leaflets. G. Flower, with sepals having fallen off. H. Sepals (left: adaxial side; right: abaxial side). I. Stamens, with anthers of the right two having dehisced. J. Carpels. K. Aggregate fruit. L. Achenes. Photographed by Y.P. Zeng.

FIGURE 10. Selected specimens of Thalictrum ramosum from Guizhou, China.A. Daozhen, Z.Y. Liu 2035759 (IMC). B. Chishui, M.C. Wang 520381160604861LY (GZTM). C. Guiyang, Wudang Exped. 520112140527028LY (GZTM). D. Xifeng, T.H. Yang 634 (GZTM).

FIGURE 11. A specimen of Thalictrum ramosum, C.M. Wang 158 (GZTM), from Dejiang in Guizhou, China, the type locality of T. minutiflorum (= T. ramosum).

FIGURE 12. Distribution of Thalictrum ramosum (●). Black arrow indicates the type locality of T. ramosum, i.e. Dujiangyan in Sichuan, China; red arrow indicates the type locality of T. minutiflorum (= T. ramosum), i.e. Dejiang in Guizhou, China.