Saxifraga viridiflora X.J.Zhang, T.Deng, J.T.Chen & H.Sun, 2021

Zhang, Xin-Jian, Fu *, Quan-Sheng, Chen, Jun-Tong, Li, Li-Juan, Luo, Peng-Rui, Peng, Jing-Yi, Huang, Xian-Han, Sun, Hang & Deng, Tao, 2021, Saxifraga viridiflora (Saxifragaceae), an unusual new species from Guangxi, China, PhytoKeys 184, pp. 19-26 : 19

Saxifraga viridiflora X.J.Zhang, T.Deng, J.T.Chen & H.Sun sp. nov.

Figs 1 , 2

Type.

China. Guangxi: Guilin City, Yongfu County, Baishou Town , 109°46'58.99"E, 25°5'15.5"N, 586 m alt., 27 June 2021, X.J. Zhang, D.X. Luo Zhangxj 98 (Holotype: KUN!; Isotypes: JIU!, SYS!) .

Diagnosis.

Saxifraga viridiflora is easily distinguished from any other species of Saxifraga sect. Irregulares by having greenish petals (vs. white petals). S. viridiflora morphologically resembles S. epiphylla and S. kegangii , but is distinct from the latter two in its leaf blade abaxially scarlet with white spots (vs. abaxially greenish/reddish with brown or yellow-green spots), and sepals with verruculose surface (vs. sepals without verruculose surface) (Table 1 ).

Description.

Perennial herbs, 12-30 cm tall. Stolons absent. Rhizomes rather short. Leaves all basal; petiole 5-12 cm long, crisped villous dark-purple (ca. 6 mm); leaf blade reniform, thick leathery, 2.5-4.0 cm long × 3.5-5.3 cm wide, base cordate, margin undulate, apex obtuse, both surfaces crisped villous dark-purple (5.0-9.0 mm long), adaxially greenish, abaxially purple or dark red, with white spots. Inflorescence paniculate, ca. 20 cm long. 5-10-flowered; branches 2.0-3.0 cm long, glandular pubescent, 1-2-flowered; pedicels slender, 1.0-2.0 cm long, glandular pubescent. Flowers zygomorphic; sepals 5, spreading to reflexed, narrowly ovate, 2.5-3.5 mm long × 1.5-2 mm wide, glabrous, abaxially red, with white verruculose, adaxially greenish, 3-5-veined, apex obtuse. Petals 5, greenish, margin entire, glabrous, apex acute; the three smallest lanceolate, 3.0-4.0 mm long × 1.0-1.2 mm wide, 3-veined; the two largest lanceolate oblong, 0.7-1.4 cm long × 1.0-1.2 mm wide, 3-veined. Stamens 10, 3.2-4.0 mm long. Ovary ovoid, 1.5-2.0 mm long, disc obscure; styles divergent ca. 1.0-1.8 mm long. Capsule beaks winged when mature, carpels 5-7 mm long × 3-4 mm wide. Seeds elliptic, the two sides slightly bent, ca. 0.6 mm long.

Etymology.

The specific epithet refers to the flowers of this new species that are green throughout the flowering period, differing from those of all other known Saxifraga sect. Irregulares species. The Chinese name is given as “绿花虎耳草” (lǜ huā hǔ ěr cǎo), referring to the greenish petals of the new species.

Phenology.

In a two year personal observation of this new species in its native range, Guangxi. Guilin City (Luo Dexuan, pers. comm.), S. viridiflora was flowering from April to July and fruiting from June to August.

Distribution and ecology.

The new species, Saxifraga viridiflora , is currently known only from Yongfu County, Guangxi Province, China. It was observed to grow on dry limestone under dense jungles at altitudes between 500 and 600 m.

Paratypes.

China. Guangxi. Guilin City, Yongfu County, Baishou Town, 109°46'49.3"E, 25°5'16.1"N, 547 m alt., 10 July 2021, X.J. Zhang, L.J. Li, J.Y. Peng, P.R. Luo Deng12030 (KUN); same locality, 575 m alt., 27 June 2021, X.J. Zhang, D.X. Luo Zhangxj99 (KUN).

Figures

Figure 1. Saxifraga viridiflora X. J. Zhang, T. Deng, J. T. Chen & H. Sun, sp. nov. A flower, petals 5, greenish B fruit, capsule winged when mature C inflorescence D infructescence E pedicels glandular pubescent; sepals red, glabrous, abaxially white verruculose F adaxial leaf surface dark green, crisped villous G, J abaxial leaf surface scarlet, with white spotted, crisped villous H rhizomes crisped villous, petiole base unsheathed I petiole with crisped villous K, L plants and habitat.

Figure 2. Photograph of the holotype of Saxifraga viridiflora X. J. Zhang, T. Deng, J. T. Chen & H. Sun, sp. nov. (Zhangx 98, KUN 1519096).