Gentiana crassicaulis Duthie ex Burkill

Perennials 25-40 cm tall. Roots to 30 × 2 cm. Stems ascending, stout, simple, glabrous. Basal leaves petiole 5-8 cm, membranous; leaf blade narrowly elliptic to ovate-elliptic, 12-20 × 4-6.5 cm, base narrowed, margin scabrous, apex acute, veins 5-7. Stem leaves 3-5 pairs, distinctly larger toward apex, sessile, spreading, and surrounding flower cluster; petiole to 3 cm, membranous, completely connate; leaf blade ovate-elliptic to ovate-triangular, 6-16 × 3-4.5(-7) cm, base obtuse to truncate, margin scabrous, apex acute to obtuse, veins 3-5. Inflorescences crowded, many-flowered terminal clusters, rarely also few-flowered axillary whorls. Flowers sessile. Calyx tube spathelike, 4-6 mm, membranous, split on 1 side, apex truncate; lobes 1-5, dentiform, 0.5-1 mm. Corolla blue-purple, base pale yellow base or sometimes white or dark green, urceolate, 2-2.2 cm; lobes ovate-triangular, 2.5-3.5 mm, margin entire, apex acute; plicae triangular, 1-1.5 mm, oblique, margin denticulate, apex acute. Stamens inserted at middle of corolla tube; filaments 6-8 mm; anthers narrowly ellipsoid, 1.5-2.5 mm. Style 2-2.5 mm; stigma lobes oblong. Capsules sessile, ovoid-ellipsoid, 1.8-2 cm. Seeds light brown, ellipsoid, 1.2-1.5 mm. Fl. and fr. Jun-Nov.

NW Guizhou, W Sichuan, SE Xizang, NW Yunnan

* Wastelands, grasslands, roadside slopes, alpine meadows, scrub, forest margins, forests; 2100-4500 m.

Flowering and fruiting from June to November.

Gentiana crassicaulis is close relative of Gentiana tibetica, but differs from the latter in its corolla 2-2.2 cm, blue-purple, basally pale yellow (vs. 2.6-3.2 cm, pale yellow or yellow-green).

Gentiana crassicaulis is occurring in NW Guizhou, W Sichuan, SE Xizang, NW Yunnan of China.

Gentiana crassicaulis Duthie ex Burk. and G. tibetica King ex Hook. f. are confusing gentians. The former has smaller corolla and blue-purple limbs whereas the latter has larger corolla and purple-brown limbs. Intermediate types are often found in southeast Xizang where both species are putatively considered to occur. By comprehensively compared morphological variations, chromosome numbers, and sequences of two DNA fragments (cpDNA trnS-G and nuclear ITS) from populations of the intermediate types and those of the two typical species (Zhang et al., 2006). Results indicated that corolla size is highly correlated with ploidy level. The populations of typical G. crassicaulis from Yunnan were diploid (2n=26) with small corolla while those of G. tibetica from western Xizang were tetraploid (2n=52) with large corolla. The populations of the intermediate types from southeast Xizang were tetraploid with large corolla, and a few individuals with purple to brown limbs. These features suggest that the intermediate types show more similarities to G. tibetica. However, DNA sequence evidence unambiguously grouped those populations with G. crassicaulis. Both nuclear and chloroplast DNA showed consistent results: the intermediate populations showed identical cpDNA and very similar ITS sequences to typical G. crassicaulis. No sequence variation beyond what occurred in typical G. crassicaulis and G. tibetica was found from multiple individuals of the intermediate types. Results demonstrated that polyploidization had contributed to the intraspecific variation in G. crassicaulis and that the tetraploid individuals of this species showed morphological convergence with tetraploid G. tibetica, which blurred the morphological delimitations of the two species in southeast Xizang. Nevertheless, molecular markers can discriminate convergence and correctly attribute the intermediate populations or individuals to the correct species circumscription.

Perennials 25-40 cm tall. Roots to 30 × 2 cm. Stems ascending, stout, simple, glabrous. Basal leaves petiole 5-8 cm, membranous; leaf blade narrowly elliptic to ovate-elliptic, 12-20 cm long, 4-6.5 cm wide, base narrowed, margin scabrous, apex acute, veins 5-7. Stem leaves 3-5 pairs, distinctly larger toward apex, sessile, spreading, and surrounding flower cluster; petiole to 3 cm, membranous, completely connate; leaf blade ovate-elliptic to ovate-triangular, 6-16 cm long, 3-6 cm wide, base obtuse to truncate, margin scabrous, apex acute to obtuse, veins 3-5. Inflorescences crowded, many-flowered terminal clusters, rarely also few-flowered axillary whorls. Flowers sessile. Calyx tube spathelike, 4-6 mm, membranous, split on 1 side, apex truncate; lobes 1-5, dentiform, 0.5-1 mm. Corolla blue-purple, base pale yellow base or sometimes white or dark green, urceolate, 2-2.2 cm; lobes ovate-triangular, 2.5-3.5 mm, margin entire, apex acute; plicae triangular, 1-1.5 mm, oblique, margin denticulate, apex acute. Stamens inserted at middle of corolla tube; filaments 6-8 mm; anthers narrowly ellipsoid, 1.5-2.5 mm. Style 2-2.5 mm; stigma lobes oblong. Capsules sessile, ovoid-ellipsoid, 1.8-2 cm. Seeds light brown, ellipsoid, 1.2-1.5 mm.

The chromosomal number of Gentiana crassicaulis is 2n = 26 (Yuan, 1993; Lu, 1996; Yuan et al., 1998).

Growing in wastelands, grasslands, roadside slopes, alpine meadows, scrub, forest margins, forests; 2100-4500 m.