Thalictrum secundum Edgeworth (1846: 26)

Zeng, You-Pai, Yuan, Qiong & Yang, Qin-Er, 2022, Thalictrum virgatum var. obtusifolium (Ranunculaceae), a new synonym of T. virgatum, with the new record of the morphologically similar Himalayan species T. secundum for China, Phytotaxa 570 (2), pp. 193-208 : 202-207

Thalictrum secundum Edgeworth (1846: 26) . Figs. 7‒9 .

Type:— INDIA. Himachal Pradesh: Chúr (= Choor), Badhrinath , alt. 11000‒13000 ft., in rupibus, 1844, M.P. Edgeworth 16 (holotype K000694162!). Fig. 9 .

Description:—Perennial herbs. Roots fibrous. Stem 30‒90 cm tall, distally branched, pendulous. Leaves 1‒2-ternate, subsessile; blade triangular, 2‒5 cm long, 1.5‒3 cm broad; leaflets broadly obovate, obliquely broadly obovate, suborbicular or broadly ovate, 0.5‒2 cm long, 0.5‒2 cm broad, herbaceous, adaxially green to glaucous, abaxially glaucous to whitish, base cuneate, rounded or subcordate, apex obtuse or acute, inconspicuously 3-lobate to deeply 3-lobate or incised; lobes entire or 1‒2-dentate, apex obtuse or acute; veins flat adaxially, slightly raised abaxially; stipules free, obliquely oblong, membranous, margin dentate. Inflorescence a panicle. Pedicels 0.5‒1 cm long. Flowers bisexual, drooping. Sepals 4, narrowly elliptic, 3‒4 mm long, 1.5‒2 mm broad, purplish; basal nerves 3‒5, simple or branched. Stamens 10‒15, 7‒10 mm long; filaments filiform, 4‒6.5 mm long, purplish; anthers linear, 3‒3.5 mm long, ca. 0.5 mm broad, apex obtuse or mucronate, yellowish tinged with brick-red. Carpels 5‒8, ca. 2.5 mm long, sparsely glandular-pubescent, sessile; ovary obliquely obovate, ca. 1 mm long; style ca. 1.5 mm long, straight; stigma narrowly triangular, winged, purplish. Achenes 4‒5 mm long, sparsely glandular-pubescent, subsessile; body obliquely obovate, shallowly ribbed, flattened-compressed; style persistent, straight.

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

Distribution and habitat:— Thalictrum secundum is distributed in Afghanistan, China (southern Xizang), northwestern and northeastern India, Nepal, and northern Pakistan ( Fig. 11 ). It grows on damp cliffs in ravines, forests or at forest margins at elevations of 2300‒4000 m above sea level. This species is reported here for China for the first time.

Additional specimens examined:— CHINA. Xizang: Gyirong, Y.H. Tan et al. XTBG-HIM0913 (HITBC), L. Wang, X.Q. Guo & Y.P. Zeng 2728 (IBSC), L. Wang, X.Q. Guo & Y.P. Zeng 2750 (IBSC).

INDIA. Himachal Pradesh: Kulu, M.P. Edgeworth 1055 (K), J.R. Drummond 8323 (BM, K), R.A.M. Geesteranus 14074 (K). Jammu & Kashmir: Kioonthul, J.F. Royle s.n. (E); Pahalgam, R.R. Stewart 5961 (K), R.R. Stewart 9403 (K), R.R. Stewart 23239 (K). Precise locality unknown, J.R. Reid s.n. (E), J.L. Stewart s.n. (E), T. Thomson s.n. (K). Punjab: Bashahr, J.H. Lace 401 (E, K); Chamba, J.H. Lace 1462 (E), J.H. Lace 1663 (E); Chenab, B.H. Banden-Powell 41 (K); Lahul, N.L. Bor 15506 (K), W. Koelz 867 (NAS, P). Sikkim: R.E. Cooper 477 (E). Uttarakhand: Dehradun, J.S. Gamble 27321 (K), K. Nand 189 (E), M.B. Raizada 7404 (E); Garhwal, G.E. Benham s.n. (BM), J.F. Duthie 767 (K), M.P. Edgeworth 17 (K), Herb. Falconer 15 (K, L, P); Kumaon, J.F. Duthie 52780 (K), R. Strachey & J.E. Winterbottom 5 (K, P).

NEPAL. Baglung: between Farkama and Yamakhar, H. Tabata et al. 3736 (BM, KUN). Gorkha: Lungdang Gompa, M. Suzuki et al. 9470254 (E, TI). Jumla: Maharigaon, O. Polunin, W.R. Sykes & L.H.J. Williams 190 (BM, E). Precise locality unknown, J.F. Duthie 5277 (K).

PAKISTAN. Hazara: Changla Gali, R.R. Stewart s.n. (K); Dunga Gali, R.R. Stewart 26450a (E), R.R. Stewart 28782a (E).

Notes:—According to Riedl & Nasir (2011) and Ghimire et al. (2021), Thalictrum pauciflorum Royle (1834: 52) , T. macrostigma Edgeworth (1846: 26) , T. hazaricum Qureshi & Chaudhri (1979: 11) , and T. secundum var. hazaricum Riedl (1979: 361) should all be placed in synonymy with T. secundum . We have checked the type material of all these names and accept the treatment.

Figures

FIGURE 7. Specimens of Thalictrum secundum from Gyirong in southern Xizang, China. A, B. L.Wang, X.Q. Guo & Y.P. Zeng 2750 (IBSC).

FIGURE 8. Thalictrum secundum in the wild (Gyirong in southern Xizang, China). A. Habitat. B. Habit. C. Roots. D. Portion of stem. E. Leaves (left: adaxial side; right: abaxial side). F. Leaflets (left: adaxial side; right: abaxial side). G. Flowers. H. Sepals (adxial side). I. Stamens. J. Carpels. K. Aggregate fruit. L. Achenes (immature). A, B, E, K, L: photographed by Y.P. Zeng; C, D, G‒J: photographed by H.B. Ding; F: photographed by H.H. Xi.

FIGURE 9. Holotype sheet of Thalictrum secundum.

FIGURE 11. Distribution of Thalictrum virgatum and T. secundum. Arrow indicates the type locality of Thalictrum virgatum var. obtusifolium (= T. virgatum), i.e. Binchuan in northwestern Yunnan, China.