Chenopodium bengalense (Lam.) Spielm. ex Steud., Nomencl. Bot., ed. 2, 1: 348 (1840)

Sukhorukov, Alexander P., Liu, Pei-Liang & Kushunina, Maria, 2019, Taxonomic revision of Chenopodiaceae in Himalaya and Tibet, PhytoKeys 116, pp. 1-141 : 25-26

6. Chenopodium bengalense (Lam.) Spielm. ex Steud., Nomencl. Bot., ed. 2, 1: 348 (1840)

≡ Atriplex bengalensis Lam., Encycl. 1(1): 276 (1783). Lectotype (designated by Sukhorukov and Kushunina 2014): "Plante potagére des Indes [vegetable plant from India], herb. De Lamarck" (P-LA00381128!). Epitype (designated by Sukhorukov and Kushunina 2014): NEPAL, [Dhaulagiri zone, Myagdi distr.] Annapurna conservation area, near Tikhedhunga vill., 1700 m alt., edge of vegetable garden, 13 Nov 2008, A. Sukhorukov s.n. (MW! isoepitype W2010-0007930!). All branches of the epitype and isoepitype are from one individual.

= Chenopodium giganteum D.Don, Prodr. Fl. Nepal.: 75 (1825). Lectotype (designated by Sukhorukov and Kushunina 2014): Herb. Wallich 6952 F [N. Wallich] (K!).

= Chenopodium album L. subsp. amaranticolor H.J.Coste & Reyn., Bull. Herb. Boissier, sér. 2, 5: 979 (1905). Type: n.v.

≡ Chenopodium amaranticolor (H.J.Coste & Reyn.) H.J.Coste & Reyn., Bull. Soc. Bot. France 54: 181 (1907).

Taxonomic notes.

The correct name for this taxon previously known as Chenopodium giganteum was reinstated by Sukhorukov and Kushunina (2014), but the year of Spielmark’s combination Chenopodium bengalense (Lam.) Spielm. in Steudel (1821) is wrong, because Spielmark considered Chenopodium bengalense (Lam.) Spielm. as a synonym of Atriplex bengalense Lam. The combination Chenopodium bengalense is indeed validated in Steudel (1840).

Description.

Robust annual up to 2.5 m, branched from the base. Petioles of lower caducous leaves up to 10 cm, blades 10-25(30) × 5-10 cm, usually rhombic, dentate, erose or trilobate with elongated terminal lobe; middle leaves rhombic or ovate, smaller; upper leaves oblong or lanceolate, completely entire, abaxially grey; young leaves often reddish. Inflorescence whitish due to the presence of abundant bladder hairs on the branches and perianth. Fruit 1.2-1.5 mm, pericarp hyaline, adjoining to the seed coat, but separating from it when rubbed, long-papillate in fresh or even dry fruits (Fig. 8D ). Seed black, ± keeled, with small crater-like micro-depressions (Fig. 8E, F ).

Habitat.

Edges of vegetable gardens and other places with secondary vegetation; 700-2900 m a.s.l. Cultivated as a crop but very locally.

Phenology.

Flowering: June-September; fruiting: August-November.

Distribution.

See Fig. 9 .

Specimens examined.

CHINA: Xizang: Nyingchi Prefecture: Motuo [ Mêdog] County, Galasha to Shuina, 1700 m a.s.l., 18 Nov 1982, Cheng & Li 03053 (PE00510185, PE00510186); Nyingchi (Linzhi) County, Bayi Town, 2950 m a.s.l., 20 Jun 1989, K.Yao et al. 1298 (NAS00003754);

INDIA: Himachal Pradesh: Upper Kinnaur, Poari, 21 Sep 1890, J.H. Lace 623 (E, G); Uttarakhand: Tehri Garhwal [Distr.], Jhala, 8000-9000 ft a.s.l., 25 Jun 1853, J.F. Duthie s.n. (DD, G); Sikkim: Sikkim Himal [without date and collector] (K);

NEPAL: Western: Dhaulagiri Zone: [Baglung Distr.] nr Lumsum, 8000 ft a.s.l., 10 Sep 1954, J. Stainton, W.R. Sykes & L.H.J. Williams 4315 (BM; LE); [Myagdi Distr.] between Ramche & Gram, 1800-1900 m a.s.l., 20 Aug 1972, Kanai et al. 723625 (BM); [Myagdi Distr.] Annapurna conservation area, near Tikhedhunga vill., 1700 m a.s.l., 13 Nov 2008, A. Sukhorukov s.n. (MW, W2010-0007930); Central: Bagmati Zone: Nuwakot Distr., Bidur, anonym s.n. (KATH); [Rasuwa Distr.] Dhunche, 2000 m a.s.l., 22 Aug 1972, Kanai et al. 723624 (BM).

General distribution.

Himalaya and Tibet and as casual alien in some parts of Eurasia ( Uotila 1997; 2001). The specimens from Eastern China labelled as Chenopodium giganteum (PE, see also Zhu et al. 2003) do not belong to C. bengalense . The easternmost records of C. bengalense are known from Sichuan, Guizhou, Shensi and Shaanxi provinces in China (PE!).

Figures

Figure 8. SEM micrographs of Chenopodium fruits and seeds. A pericarp surface of C. karoi B, C seed of C. karoi D fruit of C. bengalense enclosed in perianth E, F seed of C. bengalense. Magnification: 350 x (A), 50 x (B, D, E), 200 x (C, F).

Figure 9. Distribution map of Chenopodium bengalense (circles), C. novopokrovskyanum (triangles) and C. atripliciforme (stars).