Thalictrum megalostigma ( Boivin 1944: 363 ) Wang (1980: 27)

Zeng, You-Pai, Yuan, Qiong & Yang, Qin-Er, 2021, Thalictrum kangdingense (Ranunculaceae), a new synonym of T. megalostigma from China, Phytotaxa 498 (2), pp. 87-103 : 88-103

Thalictrum megalostigma ( Boivin 1944: 363) Wang (1980: 27) . Figs. 1 , 4 ‒ 9 , 12 , 13 .

≡ T. baicalense var. megalostigma Boivin (1944: 363) .

Type:— CHINA. Sichuan: Kangtin-hsien (Tatsienlu) (= Kangding), in thickets, 9000 ‒ 9500 ft, 27 September 1928, W. P. Fang 3619 (holotype GH00038599 !; isotypes E00386259 !, K000694181 !, NAS00186902 !, P00145842 !, US00103795!). Fig. 4 .

= T. kangdingense Wang (2020: 5) , syn. nov.

Type:— CHINA. Sichuan: Kangding, Bawanghai , in forests, 3137 m, 17 July 2018, X. Y. Zhu et al. GG226 (holotype PE02293701 !). Fig. 1 .

Description:—Perennial herbs, glabrous throughout. Roots fibrous. Stem 40–120 cm tall. Basal leaves persistent at anthesis. Cauline leaves 2–4-ternate; leaf blade pentagonal, 7–32 cm long, 7–30 cm broad; leaflets ovate or broadly ovate, 1.5– 6 cm long, 0.7– 6 cm broad, base rounded or subcordate, apex obtuse, acute or mucronate, 3-lobate; lobes 2 ‒ 3-lobate or entire, apex rounded; nerves 5, obscure adaxially, prominent abaxially; petioles 2–15 cm long, with stipules at base; stipules oblong, membranous, margin torn. Inflorescence thyrsiform, leafy. Flowers bisexual, erect. Sepals narrowly obovate, ca. 3 mm long, margin membranous. Stamens 11 ‒ 16; filaments ca. 5 mm long, proximally filiform, distally oblanceolate-linear, white; anthers ca. 1 mm long, ovate, apex obtuse, pale yellow. Carpels 4–7, subsessile; ovary compressed-ellipsoid, smooth; style ca. 1 mm long, uncinate or circinate; stigma linear. Achene stipe ca. 0.5 mm long; body broad-ellipsoid, inconspicuously ribbed when dry; style persistent, apex recurved.

Phenology:—Flowering from June to July; fruiting from July to August.

Distribution and habitat:— Thalictrum megalostigma is endemic to China (southeastern Gansu and northern and western Sichuan) ( Fig. 14 ). It grows in forests, bushes or on grassy slopes at altitudes of 1900–3200 m above sea level.

Additional specimens examined:— CHINA. Gansu: Lintan, X.G. Sun et al. 2280 (PE01801100); Tanchang, T.P. Wang 14344 (KUN0689930, PE00471247, WUK, barcode unavailable); Tewo, Q.E. Yang & H.Z. Kong 98-87 (PE00471480). Sichuan: Baoxing, K.C. Kuan & W.T. Wang 3002 (PE00450910, PE00450911); Barkam, D.E. Boufford et al. 39874 (PE01859674), Sichuan Med. Plant Exped. 22283 (NAS00186965); Danba, D.E. Boufford et al. 37958 (PE01859675), FLPH Sichuan Exped. 152758 (PE02283024, PE02283025, PE02283046), S. Jiang et al. 2210 (PE00450904), S. Jiang et al. 9738 (PE00450813, PE00450899), H. Li 5503 (PE00450903, SZ00091964); Dawu, T.J. Tong & M. Tang 247 (IBSC, barcode unavailable); Hongyuan, Z.Y. Zhang & H.F. Chow 22825 (KUN0690577, NAS, barcode unavailable, NAS00186904, PE00450907, SZ00091965, SZ00091966); Jinchuan, Anonymous 454 (SM, barcode unavailable, SM704604832), D.E. Boufford et al. 38806 (PE01859676), H. Li 2447 (IBSC0090191, PE00450902, SZ00091963), H. Li 77615 (NAS00187365), H. Li 77671 (IBSC0090359, NAS, barcode unavailable, NAS00187364, PE00450908, PE00471248, WUK, 2 sheets, barcodes unavailable), H. Li 77675 (IBSC0090360, NAS, barcode unavailable, NAS00187363, PE00450909, WUK, barcode unavailable); Jiuzhaigou, Anonymous 677 (SM, barcode unavailable, SM704604833), M. Tamura et al. 766 (CDBI0026486); Kangding, W.K. Hu & C. Ho

11289 (PE00450900, SZ00092336), K.Y. Lang, L.Q. Li & Y. Fei 1073 (KUN0689931, PE01108886, PE01108887), C.S. Liu 734 (IBSC0090117, PE00471249, PE00471250, PE00471251, SZ00091962), Y.L. Peng, W.G. Tu & C.L. Yu 701 (CDBI0207054, CDBI0207056), H.L. Tsiang 36784 (PE00450901, SZ00091959), Y.P. Zeng & Q.L. Huang 362 (IBSC, barcode unavailable), Y.P. Zeng & Q.L. Huang 366 (IBSC, barcode unavailable); Lixian, S.Y. Chen, C. Ho & M.F. Zhong 5337 (SM, barcode unavailable, SM704604451, SZ00091967), D.P. Ho 44381 (SZ00092337, SZ00092339, SZ00092340), D.P. Ho 44674 (SZ00091951, SZ00091960, SZ00091961), D.P. Ho 44905 (SZ00091952, SZ00091954, SZ00091955, SZ00091956, SZ00091957, SZ00091958), D.P. Ho 46503 (PE00470065, SZ00091949, SZ00091950, WUK, barcode unavailable), Q. Wang & K. Yao 99172 (PE00875570), C.L. Wu 33545 (NAS00186903, PE00450905); Pingwu, Anonymous 274 (CDBI0026469, CDBI0026470); Precise locality unknown, Sichuan Exped. 47 (E, barcode unavailable); Xiaojin, S.S. Chang & Y.X. Ren 7054 (PE00450906, SZ00092338), K.Y. Lang, L.Q. Li & Y. Fei 1519 (KUN0690917, PE01108888, PE01108889), F.T. Wang 21377 (GH00110304, IBSC0090119, KUN0689152, LBG00051822, NAS00070703, NAS00186898, NAS00186901, PE00028212, PE00028213, PE00028214, PE00028215, WUK, barcode unavailable); Zoige, W.H. Li et al. H82-511 (PE00477946, PE00477947, PE00477948, PE00477949).

Figures

FIGURE 1. Holotype sheet of Thalictrum kangdingense (= T. megalostigma). Inset: flower.

FIGURE 4. Holotype (A) and isotype (B‒D) sheets of Thalictrum megalostigma. A. Inset: aggregate fruit. B. Inset: aggregate fruit.

FIGURE 5. Paratype sheets (A‒D) of Thalictrum megalostigma. A. Inset: flower. B. Inset: flower.

FIGURE6. SelectedspecimensofThalictrummegalostigma.A.China,Gansu province,Tanchangcounty,T.P.Wang14344(KUN0689930). B. China, Sichuan province, Danba county, D.E. Boufford et al. 37958 (PE01859675). C. China, Sichuan province, Jinchuan county, D.E. Boufford et al. 38806 (PE01859676). D. China, Sichuan province, Barkam county, D.E. Boufford et al. 39874 (PE01859674).

FIGURE 7. Selected specimens of Thalictrum megalostigma from Kangding county in Sichuan province, China. A. W.K. Hu & C. Ho 11289 (PE00450900). B. H.L. Tsiang 36784 (PE00450901). C. K.Y. Lang, L.Q. Li & Y. Fei 1073 (PE01108887). D. C.S. Liu 734 (PE00471249).

FIGURE 8. A specimen of Thalictrum megalostigma, Y.P. Zeng & Q.L. Huang 366 (IBSC), from the type locality, i.e. Kangding county in Sichuan province, China.

FIGURE 9. Thalictrum megalostigma in the wild (China, Sichuan province, Kangding county, the type locality).A. Habitat. B. Habit. C. Roots. D. Portion of stem. E. Leaf (left: adaxial side; right: abaxial side). F. Leaflet (left: adaxial side; right: abaxial side). G. Flower. H. Stamens. I. Carpels. J. Aggregate fruit. K. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 12. A specimen of Thalictrum kangdingense (= T. megalostigma), Y.P. Zeng & Q.L. Huang 362 (IBSC), from the exact type locality, i.e. Bawanghai in Kangding county in Sichuan province, China.

FIGURE 13. Thalictrum kangdingense (= T. megalostigma) in the wild (China, Sichuan province, Kangding county, Bawanghai, the exact type locality of T. kangdingense). A. Habitat. B. Habit. C. Roots. D. Portion of stem. E. Leaf (left: adaxial side; right: abaxial side). F. Leaflet (left: adaxial side; right: abaxial side). G. Flower. H. Sepal (left: abaxial side; right: adaxial side). I. Stamens. J. Carpels. K. Aggregate fruit. L. Achenes (immature). Photographed by Y.P. Zeng.

FIGURE 14. Distribution of Thalictrum megalostigma (●). Arrow indicates the type locality of T. kangdingense (= T. megalostigma) and T. megalostigma, i.e. Kangding county in Sichuan province, China.