Thalictrum reniforme Wallich (1831: 26)

Zeng, You-Pai, Yuan, Qiong & Yang, Qin-Er, 2022, Thalictrum cuonaense (Ranunculaceae) is merged with the Himalayan T. reniforme, with notes on its morphologically similar species, Phytotaxa 554 (3), pp. 221-244 : 222-242

Thalictrum reniforme Wallich (1831: 26) . Figs. 1‒9 , 12 , 13 .

Type:— NEPAL. Rasuwa: Gossain Than , Wallich Cat. 3716 (lectotype K000694163 !, designated here ; isolectotypes BM000521586 !, K001119882 (in part) !; see below for discussion). Figs. 12 , 13 .

= T. cuonaense Wang (2014: 791) , syn. nov.

Type:— CHINA. Xizang: Cona county, Lebu town, Lebu tea plantation, bush-grassland on slope, 2500 m, 4 October 1981, Z.J. Ren 364 (holotype PE02068028!; isotype PE00875628!). Fig. 1 .

Description:—Perennial herbs. Roots fibrous. Stem to 150 cm tall, distally branched, proximally glabrous or subglabrous, distally glandular-pubescent. Leaves 2‒3-pinnate-ternate; blade triangular, 5‒20 cm long, 4‒18 cm broad; leaflets suborbicular, broadly ovate, orbicular-ovate or broadly rhombic-obovate, 1‒2.5 cm long, 1‒3.2 cm broad, herbaceous, subglabrous to densely glandular-pubescent on both sides, green on adaxial side, pale green on abaxial side, base rounded or subcordate, apex obtuse or acute, 3-lobate; lobes entire or 2‒3-lobate, apex obtuse or acute; veins submerged adaxially, slightly raised abaxially; petioles 1.5‒6 cm long; stipules sheath-like, narrow, membranous, margin entire. Inflorescence paniculiform, many-flowered; rachis subglabrous to densely glandularpubescent. Pedicels ca. 2 cm long, subglabrous to densely glandular-pubescent. Flowers bisexual, drooping. Sepals 4, broadly elliptic or ovate, 7‒17 mm long, 4.5‒10 mm broad, usually purple, very occasionally recorded to be white (?), abaxially subglabrous to densely glandular-pubescent. Stamens 20‒30, 6‒13 mm long; filaments filiform, ca. 3‒6 mm long, distally minutely glandular-pubescent, purplish; anthers linear, 3‒6 mm long, ca. 0.6 mm broad, apex obtuse to mucronate, pale yellow. Carpels 10‒20, ca. 3 mm long, subglabrous to densely glandular-pubescent, sessile to conspicuously stipitate; stipe to 0.5 mm long; ovary obliquely obovate, ca. 1.5 mm long, greenish; style 1.2‒2 mm long, straight; stigma conspicuous, oblong, ca. 0.5 mm long, purplish. Achenes 6‒9 mm long, sparsely to densely glandular-pubescent, subsessile to conspicuously stipitate; stipe to 2.5 mm long; body basally cuneate-attenuate, flattened-compressed, obliquely broadly obovate; style persistent, straight.

Phenology:—Flowering from July to October; fruiting from August to November.

Distribution and habitat:— Thalictrum reniforme is widely distributed in the Himalayan region, including Bhutan, China (southern Xizang), northeastern India (Sikkim), and Nepal ( Fig. 11 ). It grows in bushes, forests, or on grassy slopes at elevations of 2400–4000 m above sea level.

Typification:— Thalictrum reniforme was described on the basis of a single collection, Wallich Cat. 3716 (BM, K; Figs. 12 , 13 ). We have been able to trace three sheets of this collection, with two at K (barcodes K000694163, K001119882; Figs. 12 , 13A ) and one at BM (barcode BM000521586; Fig. 13B ). Upon careful examination of these sheets, we found that the K001119882 sheet consists of two taxa. This sheet contains four plant fragments. The left, middle-upper and right ones indeed belong to T. reniforme , but the middle-lower one, with the stem being subglabrous (vs. densely glandular-pubescent in the other three fragments), the stipules being broadly auricular (vs. narrowly sheathlike in the other three fragments), the leaflets also being much larger (up to ca. 4 cm long and broad vs. 2.5 cm long and broad in the other three fragments), and the sepals being ca. 4.5 mm long (vs. 10‒13 mm long) ( Fig. 13A ), should be referred to T. neurocarpum Royle (1834: 51) . In fact, Wallich (1831) in the protologue of T. reniforme described the two sides of leaves, stem and branches as being covered with greyish white, very soft hairs (foliolis …., utrinque caule ramisque pube cana, mollisima obsitis), which indicates that the middle-lower fragment should not have been used to prepare the original description and thus is not the original material of T. reniforme . The K001119882 sheet (in part), the K000694163 sheet and the BM sheet are therefore syntypes as there is no evidence that only one was used to prepare the original description. In conformity with Art. 9.3 and Art. 9.11 of the Shenzhen Code ( Turland et al. 2018) and as discussed by McNeill (2014), a lectotypification is needed for T. reniforme . In the above, accordingly, the K000694163 sheet has been chosen as the lectotype, and the other two sheets cited as isolectotypes.

Additional specimens examined:— BHUTAN. Bumthang, F.Ludlow & G. Sherriff 251 (BM, barcode unavailable, E00168792), F. Ludlow & G. Sherriff 280 (BM, E00168803), F. Ludlow, G. Sherriff & J.H. Hicks 16988 (BM, barcode unavailable), F. Ludlow, G. Sherriff & J.H. Hicks 19287 (BM, barcode unavailable), F. Ludlow, G. Sherriff & J.H. Hicks 19544 (BM, barcode unavailable), F. Ludlow, G. Sherriff & J.H. Hicks 19670 (BM, barcode unavailable, E00168796). Dhur Chu, F. Ludlow, G. Sherriff & J.H. Hicks 16950 (BM, barcode unavailable, E00168801, K, barcode unavailable), F. Ludlow, G. Sherriff & J.H. Hicks 19815 (BM, barcode unavailable). Ha, R. Bedi 336 (K, barcode unavailable), B.J. Gould 1284 (K, barcode unavailable). Khoma Chu, F. Ludlow, G. Sherriff & J.H. Hicks 20878 (BM, barcode unavailable), F. Ludlow, G. Sherriff & J.H. Hicks 21279 (BM, barcode unavailable). Loona, F. Ludlow, G. Sherriff & J.H. Hicks 16610 (BM, barcode unavailable). Mo Chu, F. Ludlow, G. Sherriff & J.H. Hicks 17352 (BM, barcode unavailable), S.B. Lyon 13072 (E00148718), C. Sargent 37 (E00168790). Pangotang Tsampa, F. Ludlow, G. Sherriff & J.H. Hicks 19262 (BM, barcode unavailable). Phoji Ding, R. Bedi 579 (K, barcode unavailable), R. Bedi 582 (K, barcode unavailable). Rinchen Chu, F. Ludlow & G. Sherriff 3451 (BM, barcode unavailable, E00168802). Thimphu, Bigger 2967 (E00168788), R.E. Cooper 1799 (BM, barcode unavailable, E00168799), R.E. Cooper 3093 (E00168793, E00168800), R.E. Cooper 3208 (BM, barcode unavailable, E00168797), R.E. Cooper 3384 (E00168791), A.J.C. Grierson & D.G. Long 2753 (E00168795), S. Bowes Lyon 5004 (BM, barcode unavailable), I.W.J. Sinclair & D.G. Long 5557 (E00168789). Tongsa Dzong, B.J. Gould 604 (K, barcode unavailable), B.J. Gould 654 (K, barcode unavailable), B.J. Gould 930 (E00168794), B.J. Gould 1138 (K, barcode unavailable), A.J.C. Grierson & D.G. Long 2610 (E00168798, K, barcode unavailable). Upper Pho Chu, F. Ludlow, G. Sherriff & J.H. Hicks 16732 (BM, barcode unavailable).

CHINA. Xizang: Cona, Anonymous 75-1638 (PE00558489, PE00558495, PE00558496), FLPH Tibet Exped. 12- 0636 (PE01966760, PE01966761), FLPH Tibet Exped. 12-0879 (PE01966785, PE01966786), P.C. Kuo & W.Y. Wang 22671 (HNWP, barcode unavailable, KUN0690051), J.Luo &S.L. Wang LIUJQ11XZ156 (HNWP,barcode unavailable), PE-Xizang Exped. 6297 (PE, barcode unavailable), PE-Xizang Exped. 6533 (PE, barcode unavailable), Qinghai-Xizang Exped. 74-2830 (HNWP, barcode unavailable, KUN0690048, PE00450319, PE00450320), Qinghai-Xizang Exped. Suppl. Group 751821 (HNWP, barcode unavailable, KUN0689480, KUN0689481, PE00450312, PE00450313), Qinghai-Xizang Exped.Suppl.Group751901 (HNWP,barcode unavailable,KUN0690049,KUN0690050,PE00450310, PE00450311), C.Y. Wu et al. 75-1110 (KUN0689487); Dinggye, Anonymous 451 (PE00470108), PE-Xizang Exped. 3074 (PE, barcode unavailable), PE-Xizang Exped. 3231 (PE, barcode unavailable), PE-Xizang Exped. 3232 (PE, barcode unavailable); Gyirong, CMTTE 751 (GXMG0106229), CMTTE 807 (GXMG0106228), B.S. Li et al. 13241 (PE01040608), PE-Xizang Exped. 194 (PE01876644), PE-Xizang Exped. 558 (PE01876682), PE-Xizang Exped. 665 (PE01876642), PE-Xizang Exped. 4023 (PE, barcode unavailable), PE-Xizang Exped. 4039 (PE, barcode unavailable), PE-Xizang Exped. 4152 (PE, barcode unavailable), PE-Xizang Exped. 7903 (PE, barcode unavailable), QinghaiXizang Exped. 6358 (PE00450316), Qinghai-Xizang Exped. 7052 (HNWP, barcode unavailable, KUN0689454, KUN0689455, PE00450323, PE00450324), L. Wei & J.C. Hao 15355 (BNU0026006), L. Wei & Y. He BNUXZ2016285 (BNU0028355, BNU0028356), C.Y. Wu et al. 75-598 (KUN0690047); Lhunze, Y.S. Chen et al. 13-0584 (PE02000424, PE02000558, PE02000571, PE02000572), F. Kingdon-Ward 12342 (BM, barcode unavailable), PE-Xizang Exped. 6011 (PE, barcode unavailable), L. Wang & T.J. Tong 1272 (IBSC, barcode unavailable); Mainling, F. Ludlow, G. Sherriff & H.H. Elliot 13315 (BM, barcode unavailable), F. Ludlow, G. Sherriff & G. Taylor 5919 (BM, barcode unavailable, E, barcode unavailable), Qinghai-Xizang Exped. 74-1989 (HNWP, barcode unavailable, KUN0690046, PE00450321, PE00450322), L. Wei & Y. He BNUXZ2016438 (BNU0028321); Medog, S.Z. Cheng & B.S. Li 374 (PE, barcode unavailable), FLPH Tibet Exped. 12-1896 (PE01966757); Nangxian, F. Ludlow & G. Sherriff 2496 (BM, barcode unavailable, E, barcode unavailable); Yadong, Anonymous 75-884 (PE00558491, PE00558492), C.H. Bell s.n. (K, barcode unavailable), F.S. Chapman 425 (K, barcode unavailable), R.E. Cooper 239 (E, barcode unavailable), Dungboo 4267 (K, barcode unavailable), Dungboo s.n. (BM, barcode unavailable, K, barcode unavailable), K.H. Fu et al. 1099 (PE01040618), K.H. Fu et al. 1101 (PE, barcode unavailable), H.E. Hobson s.n. (K, barcode unavailable), X.H. Jin et al. 13252 (PE02025169), F. Ludlow & G. Sherriff 10025 (BM, barcode unavailable), PE-Xizang Exped. 1815 (PE01876700), PE-Xizang Exped. 2543 (PE, barcode unavailable), PE-Xizang Exped. 2753 (PE, barcode unavailable), Qinghai-Xizang Exped. 74-2322 (HNWP, barcode unavailable, KUN0689458, PE00450314, PE00450315), QinghaiXizang Exped. 74-2542 (KUN0689457, PE00450317, PE00450318), P.C. Tsoong 5880 (NAS, barcode unavailable, PE00450308, PE00450309), Z. Zhou et al. ZJW567 (KUN1274404).

INDIA. Sikkim: T. Anderson 329 (P00145797, P00145798), Anonymous s.n. (E, barcode unavailable, P00145809), R.H. Beddome 19 (BM, barcode unavailable), G.H. Cave s.n. (E, barcode unavailable), G.H. Cave 82-47 (E, barcode unavailable), C.B. Clarke 9852 (BM000946094), C.B. Clarke 10110 (K, barcode unavailable), C.B. Clarke 12690 (BM, barcode unavailable, K, barcode unavailable), C.B. Clarke 12691 (K, barcode unavailable), C.B. Clarke 13457 (K, barcode unavailable), C.B. Clarke 25961 (BM, barcode unavailable), C.B. Clarke 27524 (BM, barcode unavailable, K, barcode unavailable), R.E. Cooper 493 (E, barcode unavailable), J.S. Gamble 141 (K, barcode unavailable), J.S. Gamble 8408 (E, barcode unavailable, K, barcode unavailable), G.A. Gammie 367 (P00145800, U1547378), J.D. Hooker s.n. (E, barcode unavailable, K, barcode unavailable, L1734210, P00145801, P00145824, U1547379), J.D. Hooker 1199 (P00145801, P00145802), H. Kanai et al. 723335 (BM, barcode unavailable, E, barcode unavailable), H. Kanai et al. 723336 (BM, barcode unavailable, E, barcode unavailable), W.S. Kurz s.n. (L1734211, P00145810), J.H. Lace s.n. (E, barcode unavailable), R. Lepcha 10 (E, barcode unavailable, K, barcode unavailable), R. Lepcha 1186 (E, barcode unavailable), D. Lowndes 627 (E, barcode unavailable), Miehe 890 (BM, barcode unavailable), Ribu & Rhomoo 5323 (BM, barcode unavailable), Ribu & Rhomoo 6335 (E, barcode unavailable), Smith & Cave 2674 (P00145811), T. Thomson s.n. (K, barcode unavailable, L1734209, P00145805).

NEPAL. Charikot, J. Sacherer s.n. (E00821764). Gorkha, Lall Dhwoj 156 (BM, barcode unavailable, E, barcode unavailable), P.C. Gardner 915 (BM, barcode unavailable), H. Ikeda et al. 20811126 (E00640037), M. Suzuki et al. 9460214 (PE01966023), M. Suzuki et al. 9470229 (KUN1261004). Kathmandu, F.M. Bailey 75 (BM, barcode unavailable), F.M. Bailey 282 (BM, barcode unavailable), J.F. Dobremez 529 (BM, barcode unavailable, E00839644), J.F. Dobremez 1000 (E00821763), H. Kanai, H. Hara & H. Ohba 723339 (BM, barcode unavailable), Kew-Edinb.- Kathmandu Exped. 314 (E, barcode unavailable, K, barcode unavailable), A. Maire 273 (E00821730), O. Polunin 474 (BM, barcode unavailable), O. Polunin 498 (BM, barcode unavailable), O. Polunin 1572 (BM, barcode unavailable), J.D.A. Stainton 4006 (BM, barcode unavailable), J.D.A. Stainton 7228 (E, barcode unavailable), J.D.A. Stainton 7458 (E00265508), J.D.A. Stainton, W.R. Sykes & L.H.J. Williams 6374 (BM, barcode unavailable, E, barcode unavailable). Precise locality unknown, D. Chatterjee 211 (AMD98221), Lal Dhoj s.n. (K, barcode unavailable), N. Sharma 59 (BM, barcode unavailable, E, barcode unavailable, K, barcode unavailable), C. Wigram 69 (E, barcode unavailable, K, barcode unavailable). Rasuwa, T. Hoshino et al. 9539102 (TI, barcode unavailable), F. Miyamoto et al. 9400066 (BM, barcode unavailable, E00069664, E00069665, KUN0137429, KUN0137430, L4205645), F. Miyamoto et al. 9420183 (BM, barcode unavailable, E00069667, L4205646), F. Miyamoto et al. 9440102 (BM, barcode unavailable, E00069666, KUN0137431), H. Takayama et al. 9220330 (BM, barcode unavailable), H. Takayama et al. 9239206 (E00220849). Sankhuwasabha, S. Noshiro et al. 9820050 (KUN1214324, PE01900071, TI, barcode unavailable). Sindhupalchok, J.H. Haas 2157 (BM, barcode unavailable, L4200332, U1547391). Solukhumbu, J.F. Dobremez 453 (BM, barcode unavailable, E00839648), J.H. Haas 2904B (BM, barcode unavailable), Lall Dhwoj 165 (BM, barcode unavailable, E, barcode unavailable), F. Miyamoto et al. 9592096 (BM, barcode unavailable, E00071614), F. Miyamoto et al. 9592107 (BM, barcode unavailable, E00071615), F. Miyamoto et al. 9592478 (E00071601), F. Miyamoto et al. 9596080 (BM, barcode unavailable, E00071616), A.D. Schilling 974 (K, barcode unavailable), J.D.A. Stainton 1076 (E, barcode unavailable), J.D.A. Stainton 7146 (BM, barcode unavailable), M.F. Watson et al. DNEP3 AY61 (E00246527), M.F. Watson et al. DNEP3 BX101 (E00246528, E00248968). Taplejung, Damant 125 (K, barcode unavailable), J.F. Dobremez 1267 (E00821761).

Notes:— Thalictrum neurocarpum , also a Himalayan species distributed in China (southern Xizang), northwestern India, and Nepal ( Yuan et al. 2018, Zeng et al. 2020), was confused with T. reniforme by several authors, including Hooker & Thomson (1872), Lecoyer (1885), Lauener (1978), Rau (1993), Fu & Zhu (2001), Wang (2018), and Ghimire et al. (2021). All these authors placed T. neurocarpum in synonymy with T. reniforme . Yonekura (2008) also pointed out that T. neurocarpum was doubtfully distinct from T. reniforme . As clarified by Yuan et al. (2018) and Zeng et al. (2020), T. neurocarpum should be recognized as a separate/distinct species, a treatment also adopted previously by Collett (1902), Duthie (1906), Smith (1971), Hara (1979), Naithani (1990), Press et al. (2000), and Chen (2019). This species is indeed closely similar to T. reniforme in habit, leaflet shape (suborbicular or broadly ovate), achene shape (obliquely broadly obovate, compressed), and particularly in the pubescence on pedicels, ovaries and abaxial surface of leaflets (all glandular-pubescent), but differs at once by having broadly auricular (vs. narrowly sheath-like) stipules and much smaller (narrowly elliptic, 4.5‒6 mm long, 2‒2.3 mm broad vs. broadly ovate, 7‒17 mm long, 4.5‒10 mm broad), caducous, purplish-green (vs. persistent when flowering, purple) sepals ( Figs. 4‒8 ; Zeng et al. 2020). Judging from floral characters the two species might be only distantly related to each other. The floral characters (flowers small, greenish-white, no more than half an inch in diameter, and sepals falling off very early) given by Hooker & Thomson (1872) and Rau (1993) for T. reniforme actually match quite well those in T. neurocarpum . The occurrence of T. reniforme in India’s Himachal Pradesh and Uttar Pradesh recorded by Rau (1993) should be a mistake due to misidentification of specimens of T. neurocarpum . In India, based on our examination of herbarium specimens, T. reniforme is currently known only from Sikkim. Of the eight collections cited by Lecoyer (1885) under T. reniforme , we have been able to trace R. Strachey & J.E. Winterbottom 10 (BM, K, P), M.P. Edgeworth 12 (K), M.P. Edgeworth 1053 (K) and V. Jacquemont 2172 (P). These specimens, all having remarkably large, broadly auricular stipules and smaller, caducous sepals, definitely belong to T. neurocarpum .

It is worth mentioning that in the Flora of China vol. 6, Fu & Zhu (2001) placed the name “ Thalictrum menthosma Stocks ex Lecoyer ” within the synonymy of T. reniforme . The description of this name, given in handwriting by Stocks on a paper glued on the sheet of M.P. Edgeworth 1053 preserved at K ( Fig. 14 ), has actually never been formally published. Lecoyer (1885) mentioned this name in his monograph of Thalictrum and clearly stated that it was a synonym of T. reniforme . We have checked M.P. Edgeworth 1053 and determined that it should belong to T. neurocarpum . It is obvious that Lecoyer’s (1885) concept of T. reniforme includes both T. neurocarpum and T. reniforme .

The relationship between Thalictrum chelidonii Candolle (1824: 11) and T. reniforme has also been a controversial matter. Hooker & Thomson (1855) treated T. reniforme as a variety of T. chelidonii , i.e. T. chelidonii var. reniforme (Wallich) Hooker & Thomson (1855: 13) , but later they reinstated the independent specific status of T. reniforme ( Hooker & Thomson 1872) . Since then this treatment has been accepted by almost all the subsequent authors, including Lecoyer (1885), Hara (1966, 1971, 1979), Smith (1971), Wang & Wang (1979), Polunin & Stainton (1984), Wang (1985, 2000a, 2018), Ohba & Akiyama (1992), Rau (1993), Ohba & Ikeda (1999, 2000), Press et al. (2000), Fu & Zhu (2001), Wang & Liu (2016), Xie et al. (2016), and Chen (2019). Grierson (1984), however, pointed out that the distinction between T. chelidonii and T. reniforme was unclear. He treated T. chelidonii as a species aggregate (“ T. chelidonii DC. agg. ”) and placed T. reniforme within its synonymy. He further noted that Hooker & Thomson (1872) distinguished T. reniforme by its smaller greenish-white flowers but in Bhutan and Sikkim the flowers were apparently always mauve or purplish, and very variable in size. Obviously he was misled by Hooker & Thomson’s (1872) treatment, in which T. neurocarpum was confused with T. reniforme . Morphologically T. chelidonii is similar to T. reniforme in the paniculiform inflorescence and flowers with large, showy sepals, but differs by having glabrous (vs. more or less glandular-pubescent) stem and leaves (when mature), bulbils in leaf axils of the distal part of stems, usually cuneateoblong (vs. broadly ovate) terminal leaflets, glabrous (vs. more or less glandular-pubescent) inflorescence rachis, pedicels, carpels and achenes, shorter styles (ca. 0.6 mm vs. 1.2‒2 mm), and basally abruptly obtuse (vs. cuneateattenuate) bodies of carpels and achenes ( Figs. 15 , 16 ). Our careful observations on living plants of T. chelidonii in the wild revealed that this species is not glabrous throughout, with the young leaves being sparsely glandular-pubescent on abaxial side ( Fig. 15D ).

Thalictrum tamurae Kadota & Tanaka in Tanaka et al. (2010: 208) was described on the basis of two collections, J. Murata et al. 24590 (MBK, TI, TNS; Fig. 17A ) and K. Fujikawa et al. 53405 (A, MBK, TNS, TI), from Mt. Victoria in central-western Myanmar ( Fig. 11 ), with the MBK sheet of the former collection designated as holotype. In the protologue, the authors stated that T. tamurae was most closely related to T. reniforme in having larger and persistent sepals, narrowly ovate-lanceolate stigmas, and glandular-pubescent plant body, but differed by having slender (vs. robust) habit, smaller and narrowly ovate-elliptic (vs. broadly oblong) sepals, 7‒8 mm long and 3‒5 mm broad (vs. 9‒13 mm long and 6‒10 mm broad), shorter stamens (5‒6 mm vs. 8 mm), fewer carpels (6‒10 vs. 15‒20), and dorsally recurved achene bodies. Meanwhile they also stated that T. tamurae was similar to T. diffusiflorum Marquand & Shaw in Marquand (1929: 153) ( Fig. 18 ) in having slender habit but differed by having shorter and straight (vs. longer and circinate) achene beaks and pinkish purple (vs. lilac) flowers. Thanks to K. Fujikawa’s kind help, we have been able to examine the holotype of T. tamurae ( Fig. 17A ). At BM we saw a specimen, F. Kindon-Ward 22748 ( Fig. 17B ), also from Mt. Victoria in Myanmar, the type locality of T. tamurae . The latter specimen has been previously identified as T. chelidonii but this identification is wrong because all the three plant fragments are glandular-pubescent throughout and no bulbils are present in leaf axils. In these two specimens, sepals are broadly ovate (ca. 11 mm long, ca. 7 mm broad), carpels are up to 10 in number, and developed achenes are up to 9, dorsally more or less concave (recurved). In T. reniforme , the habit, size of sepals, length of stamens, carpel number, and the shape of achenes are somewhat variable between populations. The habit is either slender or robust ( Figs. 4B , 5B , 6B , 7B ), sepals are 7‒17 mm long and 4.5‒10 mm broad ( Figs. 4J , 5I , 6I , 7I ), stamens are 6‒13 mm long ( Figs. 4K , 5J , 6J , 7J ), carpels number 10‒20, and achenes are dorsally concave or convex ( Figs. 4M , 5M , 6M , 7M ). It seems that T. tamurae is only a lower-latitude ecotype of T. reniforme ( Fig. 11 ). More work is needed to clarify the identity of T. tamurae with certainty.

Figures

FIGURE 1. Holotype (A) and isotype (B) sheets of Thalictrum cuonaense (= T. reniforme), showing habit (A, B), proximal (C, E) and distal (D, F) parts of stem, adaxial side of leaflets (G, I), inflorescence rachis (H, J), pedicels (K, M), and carpels (L, N), with C, D, G, H, K and L from the holotype (A), and E, F, I, J, M and N from the isotype (B).

FIGURE 2. Selected specimens of Thalictrum reniforme from southern Xizang, China. A. Dinggye, PE-Xizang Exped. 3074 (PE). B. Gyirong, PE-Xizang Exped. 4023 (PE). C. Mainling, Qinghai-Xizang Exped. 74-1989 (KUN0690046). D. Yadong, Anonymous 75-884 (PE00558492).

FIGURE 3. Selected specimens of Thalictrum reniforme from the type locality of T. cuonaense (= T. reniforme), i.e. Cona in southern Xizang, China. A. PE-Xizang Exped. 6297 (PE). B. J. Luo & S.L. Wang LIUJQ11XZ156 (HNWP). C. Qinghai-Xizang Exped. 74-2830 (KUN0690048). D. Anonymous 75-1638 (PE00558489).

FIGURE 4. Thalictrum reniforme in the wild (China, Xizang, Cona, Lebu tea plantation, the type locality of T. cuonaense (= T. reniforme)). A. Habitat. B. Habit. C. Proximal portion of stem (subglabrous). D. Distal portion of stem (densely glandular-pubescent). E. Leaf (left: adaxial side; right: abaxial side). F. Leaflet (adaxial side). G. Portion of abaxial side of leaflet (densely glandular-pubescent). H. Portion of pedicel. I. Flower (front view). J. Sepals (abaxial side). K. Stamens. L. Carpels. M. Aggregate fruit.A, E‒G, I‒L: photographed by Y.P. Zeng; B‒D, H, M: photographed by W.Q. Fei.

FIGURE 5. Thalictrum reniforme in the wild (China, Xizang, Cona). A. Habitat. B. Habit. C. Distal portion of stem. D. Leaflet (abaxial side). E. Portion of adaxial side of leaflet (subglabrous). F. Portion of abaxial side of leaflet (densely glandular-pubescent). G. Potion of pedicel. H. Flower (lateral view). I. Sepals (abaxial side). J. Stamens. K. Carpels. L. Fruiting branchlet, showing aggregate fruits. M. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 6. Thalictrum reniforme in the wild (China, Xizang, Dinggye). A. Habitat. B. Habit. C. Leaf (left: adaxial side; right: abaxial side). D. Leaflet (left: adaxial side; right: abaxial side). E. Portion of adaxial side of leaflet (densely glandular-pubescent). F. Portion of abaxial side of leaflet (densely glandular-pubescent). G. Flower (front view). H. Flower (lateral view). I. Sepals (abaxial side). J. Stamens. K. Carpels. L. Aggregate fruit. M. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 7. Thalictrum reniforme in the wild (China, Xizang, Yadong).A. Habitat. B. Habit. C. Portion of stem (left: proximal part; right: distal part). D. Leaf (left: adaxial side; right: abaxial side). E. Leaflet (abaxial side). F. Portion of adaxial side of leaflet (densely glandularpubescent). G. Portion of abaxial side of leaflet (densely glandular-pubescent). H. Flower (front view). I. Sepals (abaxial side). J. Stamens. K. Carpels. L. Aggregate fruit. M. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 8. Thalictrum reniforme in the wild (China, Xizang, Yadong).A. Habitat. B. Habit. C. Roots. D. Portion of stem (left: proximal part; right: distal part). E. Leaf (adaxial side). F. Leaflet (left: adaxial side; right: abaxial side). G. Portion of adaxial side of leaflet (glabrous). H. Portion of abaxial side of leaflet (minutely glandular-pubescent). I. Portion of pedicel (subglabrous). J. Flower. K. Sepal (abaxial side). L. Stamens. M. Carpels. N. Aggregate fruit. O. Achenes (immature).A, C‒O: photographed by Y.P. Zeng; B: photographed by X.Q. Guo.

FIGURE 9. Specimens of Thalictrum reniforme from southern Xizang, China.A. Cona, L. Wang, X.Q. Guo & Y.P. Zeng 3147 (IBSC). B. Dinggye, L. Wang, X.Q. Guo & Y.P. Zeng 2857 (IBSC). C. Gyirong, L. Wang, X.Q. Guo & Y.P. Zeng 2737 (IBSC). D. Yadong, L. Wang, X.Q. Guo & Y.P. Zeng 2951 (IBSC).

FIGURE 11. Distribution of Thalictrum reniforme (●) and T. tamurae (▲). Arrow indicates the type locality of T. cuonaense (= T. reniforme), i.e. Cona in southern Xizang, China.

FIGURE 12. Lectotype sheet of Thalictrum reniforme.

FIGURE 13. Isolectotype sheets of Thalictrum reniforme. A. K001119882 sheet; arrow indicates the middle-lower fragment which belongs to T. neurocarpum and is not the original material of T. reniforme; inset a: stipules of the middle-lower fragment; inset b: flower of the middle-lower fragment. B. BM000521586 sheet (in part, only the right fragment).

FIGURE 14. A specimen of Thalictrum neurocarpum, i.e. M.P. Edgeworth 1053 (K) (A, B), from northwestern India, based on which the description of T. menthosma, a name never validly published, was made by Stocks in handwriting.

FIGURE 15. Thalictrum chelidonii in the wild (China, Xizang, Gyirong). A. Habitat. B. Habit. C. Bulbils in leaf axils. D. Young leaf (abaxially sparsely pubescent). E. Leaf (adaxial side). F. Leaflet (left: adaxial side; right: abaxial side). G. Inflorescence. H. Flower (front view). I. Sepal (abaxial side). J. Stamens. K. Carpels. L. Aggregate fruit. M. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 16. Thalictrum chelidonii in the wild (China, Xizang, Dinggye).A. Habitat. B. Inflorescence. C, D. Bulbils in leaf axils. E. Leaf (left: adaxial side; right: abaxial side). F. Leaflet (left: adaxial side; right: abaxial side). G. Flower (front view). H. Sepal (abaxial side). I. Stamens. J. Carpels. K. Aggregate fruit. L. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 17. Holotype sheet of Thalictrum tamurae (A) (inset a: flower; inset b: aggregate fruit) and a specimen at BM, F. Kingdon- Ward 22748 (B), from the type locality of T. tamurae, i.e. Mt. Victoria in central-western Myanmar, but identified as T. chelidonii (inset a: flower; inset b: aggregate fruit).

FIGURE 18. Thalictrum diffusiflorum in the wild (China, Xizang, Nyingchi).A. Habitat. B. Flowering plant. C. Fruiting plant. D. Portion of stem. E. Leaf (abaxial side). F. Flower. G. Sepals (abaxial side). H. Stamens. I. Carpels. J.Aggregate fruit. K.Achenes (immature).A‒C: photographed by Y.P. Zeng; D‒K: photographed by W.Q. Fei.