Cremanthodium hongshanense L. Wang, C. Ren & Q.E. Yang, 2018

Wang, Long, Ren, Chen & Yang, Qin-Er, 2018, Two new species in Cremanthodium (Asteraceae, Senecioneae) from China, Phytotaxa 360 (3), pp. 201-219 : 201-209

1. Cremanthodium hongshanense L. Wang, C. Ren & Q.E. Yang , sp. nov. Figs. 1–3 , 8 .

Type:— CHINA. Yunnan: Shangri-la (previously known as Zhongdian), Gezan , Hong Shan , 28°09 ʹ 25.47 ʺ N, 99°54 ʹ 14.79 ʺ E, alpine screes, 4500 m, 14 August 2017, L. Wang & Y. Y. Shao 1700 (holotype IBSC; isotypes KUN, PE) .

Perennial herbs, 20–45 cm tall. Stems solitary, erect, ca. 4 mm in diameter at base, proximally glabrous, distally densely blackish-brown pilose. Basal leaves petiolate; petiole to 15 cm long, base sheathed, glabrous; leaf blade reniform or suborbicular, 4–15 cm long, 4.8–17.5 cm wide, adaxially bright green, glabrous, abaxially purplish red to pale green, white puberulent, especially so along the veins, base cordate, sinus very narrow, margin regularly crenate, apex obviously 1-mucronate; palmate veins sunken adaxially, prominent abaxially. Stem leaves 1 or 2; proximal one shortly petiolate, smaller than basal leaves, base narrowly or broadly sheathed; distal one bracteal, linear, without sheath. Capitula solitary, nodding. Involucre broadly campanulate, 1.1–1.5 cm high, 1.5–3 cm in diameter, dorsally shortly black pilose; phyllaries 13–23, in 2 rows; outer phyllaries narrowly oblong, 2 mm wide, apex acute, inner ones oblong, 3.5–5 mm wide, margin broadly membranous, apex obtuse; bracts 3–7, linear-lanceolate, 5–10 mm long. Ray florets absent. Tubular florets numerous, yellow, ca. 1.2 cm long; tube ca. 2 mm long; limb narrowly cylindric, yellow, 7 mm long; style ca. 10 mm long; style branches yellow. Achenes obovoid, yellow, 4 mm long. Pappus white, ca. 8 mm long, as long as tubular corolla.

Distribution and habitat:— Cremanthodium hongshanense is currently known only from its type locality, i.e. Shangri-la in northwestern Yunnan, China ( Fig. 4 ). It grows in gravelly places on mountains at altitudes of 4400–4600 m above sea level.

Phenology:—Flowering in August; fruiting in September.

Etymology:—The specific epithet is derived from Hong Shan, a mountain in the type locality of the new species, i.e. Shangri-la in northwestern Yunnan, China.

Additional specimens examined (paratypes):— CHINA. Yunnan: Shangri-la, Gezan, Hongshan , alpine screes, 4500–4600 m, 31 August 2009, Y. S. Chen 9685 ( PE) ; Shangri-la, Gezan, Hongshan , alpine screes, 4600 m, 6 August 2009, M. Tang et al. 1256 ( IBSC) ; Shangri-la, Gezan, Wengshui–Langdu , grassy slope, 4400 m, 29 August 1988, J. S. Yang 88-318 ( KUN) .

Discussion:— Cremanthodium hongshanense is similar to C. calcicola Smith (1920: 201) ( Figs. 5–7 ), a species also occurring in Shangri-la in northwestern Yunnan, China, in the reniform basal leaves and the solitary discoid capitula, but differs by the basal leaves obviously 1-mucronate (vs. nearly rounded) at apex, the involucres dorsally green to blackish green (vs. black to brown) coloured and shortly black pilose (vs. glabrescent), the 3–7 (vs. absent or 1–4) bracts which are linear-lanceolate and 5–10 mm long (vs. clavate and ca. 3 mm long), the yellow (vs. purplish) limb of tubular florets, the yellow (vs. blackish brown) style branches, and the pappus ca. 8 mm (vs. 5 mm) long. A morphological comparison between C. hongshanense and C. calcicola is given in Table 1.

Interestingly, we found in our fieldwork that C. calcicola actually grows in alpine humid meadows ( Fig. 6 ), although its specific epithet suggests that it should prefer rocky places. In contrast, C. hongshanense grows in gravelly places on high mountains ( Fig. 2 ).

Two collections of Cremanthodium hongshanense, Y.S. Chen 9685 (PE; Fig. 8A ) and J.S. Yang 88-318 (KUN; Fig. 8B ), had been previously misidentified on the determination slips as C. atrocapitatum Good (1929: 282) , a species once largely misunderstood ( Wang et al. 2016c). Cremanthodium hongshanense is distinguishable from C. atrocapitatum by the basal leaves crenate or shallowly dentate (vs. coarsely mucronate-dentate) at margin, obviously 1-mucronate (vs. obviously emarginate) at apex, the involucres broadly campanulate (vs. hemispheric), dorsally green to blackish green (vs. dark purple) coloured and black pilose (vs. brown or purple) pilose, and the white (vs. brown) pappus. Geographically, C. atrocapitatum is distributed in Fugong, Gongshan and Weixi in northwestern Yunnan, China.

Figures

FIGURE 1. Holotype sheet of Cremanthodium hongshanense.

FIGURE 2. Cremanthodium hongshanense in the wild (Shangri-la, Yunnan, China). A. Habitat. B, C. Habit.

FIGURE 3. Cremanthodium hongshanense in the wild (Shangri-la, Yunnan, China).A, B. Portion of stem. C. Basal leaf (adaxial surface). D. Basal leaf (abaxial surface). E. Portion of leaf blade (abaxial surface), showing pubescence. F. Capitulum (top view). G. Capitulum (back view). H. Capitulum (side view). I. Outer phyllaries (abaxial surface). J. Inner phyllaries (abaxial surface). K. Tubular florets.

FIGURE 4. Distribution of Cremanthodium hongshanense (●).

FIGURE 5. Specimens of Cremanthodium calcicola. A. China, Yunnan, Shangri-la, G. Forrest 12711 (E, holotype). B. Same locality, G. Forrest 12711 (PE, isotype). C. Same locality, K.M. Feng 1762 (PE). D. Same locality, T.T. Yu 11749 (PE).

FIGURE 6. Cremanthodium calcicola in the wild (Shangri-la, Yunnan, China). A. Habitat. B, C. Habit.

FIGURE 7. Cremanthodium calcicola in the wild (Shangri-la, Yunnan, China). A. Portion of stem. B. Basal leaf (adaxial surface). C. Basal leaf (abaxial surface). D. Capitulum (top view). E. Capitulum (back view). F. Capitulum (side view). G. Outer phyllaries (abaxial surface). H. Inner phyllaries (abaxial surface). I. Tubular florets.

FIGURE 8. Specimens of Cremanthodium hongshanense previously misidentified as C. atrocapitatum. A. China,Yunnan, Shangri-la, Y.S. Chen 9685 (PE). B. Same locality, J.S. Yang 88-318 (KUN).