Epimedium pauciflorum K.C.Yen, Guihaia 14: 124. 1994

Xu, Yanqin, Liu, Linjian, Liu, Shaoxiong, He, Yiming, Li, Renqing & Ge, Fei, 2019, The taxonomic relevance of flower colour for Epimedium (Berberidaceae), with morphological and nomenclatural notes for five species from China, PhytoKeys 118, pp. 33-64 : 45

3. Epimedium pauciflorum K.C.Yen, Guihaia 14: 124. 1994 Fig. 5

Epimedium platypetalum var. tenuis B.L.Guo & P.G.Hsiao, Acta Phytotaxon. Sin. 31: 195. 1993. Type: CHINA. Sichuan: Shuixicun, Mao Xian, 1990 m, H. R. Xie 89023, (holotype: IMD! without accession number or barcode).

Type.

CHINA. Sichuan: Dagou, Maowen, 1700 m, K. C. Yen & S. L. Shao 66535 (holotype: GXMI, barcode GXMI004519!; isotype: PE, barcode PE01432167!).

Description.

Herbs 6-30 cm tall. Rhizome long creeping, 1-3 mm in diam.; sometimes creeping to 20-25 cm. Leaves basal and cauline, trifoliolate; leaflets ovate or suborbicular, 1.3-4.5 × 1.2-3.5 cm, abaxially sparsely or occasionally densely puberulent, adaxially glabrous when mature, base deeply cordate with rounded lobes nearly touching, those of lateral leaflets conspicuously unequal, margin coarsely serrate, apex acute or shortly acuminate. Flowering stem with 1 trifoliolate, occasionally 1 unifoliolate leaf or 2 alternate trifoliolate leaves. Inflorescence simple, racemose, few-flowered (ca. 2-6 flowers), 3-13.5 cm long; inflorescence axis and pedicels glandular or pubescent. Pedicel 1-2.3 cm long; bracts ovate, 0.8-1.4 mm. Flowers ca. 2-2.5 cm in diam. Outer sepals fall sooner, greenish, caduceus, narrowly obovate, ca. 4 × 3 mm; inner sepals white, faintly rose-tinged or pale rose, broadly lanceolate, ca. 12 × 5 mm, apex obtuse. Petals declined, white, white tinged with pale rose, rose, pale yellow, pale rose with the base purple yellow, horn-shaped, longer than inner sepals, blunt spurs ca. 15 mm long, expanded at base into a lamina 6 mm high. Stamens ca. 4 mm long; anthers yellow, ca. 2.5 mm long. Follicles oblong, 10-15 cm long; style rostriform. Seeds 4-6.

Distribution and habitat.

Epimedium pauciflorum is only known from the mountains of Maowen (the holotype locality, once and now divided into Maoxian, Wenchuan and Lixian) in Sichuan province, usually occurring in forest edges and weedy slopes, at high elevations approximately 1700-2600 m (Fig. 4 ).

Phenology.

Epimedium pauciflorum flowers from April to May, and fruits also from April to May.

Taxonomical remarks.

Epimedium pauciflorum is a low-growing species with a few-flowered inflorescence. Some information about the colour variation was recorded in part of the specimens. The colours of three specimens (Z. L. Kun 89022, B. L. Guo & W. K. Bao 97040, B. L. Guo 88182) were described as white, while the other two (B. L. Guo & W. K. Bao 97031 and 97032) were described as yellow. We observed a variety of colour variations; the inner sepals were white, faintly purple-tinged or pale rose, whereas the petals were white, white tinged with pale rose, rose, pale yellow, pale rose with the base purple yellow (Fig. 5 ). Among them, the pale-yellow flowers were only observed in SCJZ population. The specimens (B. L. Guo & W. K. Bao 97031 and 97032) that were with yellow flowers and the SCJZ population in this study were sampled from the same location.

All the examined specimens were with 1 trifoliolate leaf on the flowering stem uniformly. But 1 unifoliolate leaf (only in SCWC population) or 2 alternate trifoliolate leaves (only in SCJZ population) (Fig. 5 ) were also observed in our field investigation.

Additional specimens examined.

CHINA. Sichuan: Jingzhou, Maoxian, 1700 m, 16 April 1987, K. C. Yen & S. L. Shao 66535 (PE, GXMI); Jingzhou, Maoxian, 1770 m, 19 April 1997, B. L. Guo & W. K. Bao 97031 and B. L. Guo & W. K. Bao 97032 (IMD); Jingzhou, Maoxian, 1770 m, 19 April 1997, B. L. Guo & W. K. Bao 97040 (IMD); Jingzhou, Maoxian, 1800 m, 2 May 1989, Z. L. Kun 89022 (IMD); Shuishi, Maoxian, 2000 m, 19 May 1989, H. R. Xie 89023 (IMD); Jingzhou, Maoxian, 1800 m, 3 September 1988, B. L. Guo 88182 (IMD); Daheba, Maoxian, 1800 m, 6 September 1988, B. L. Guo 88195 (IMD); Mt. Bianshi (Bianshishan), Maowen, 2600 m, 22 August 1985, F. Li 822-1 (IMD); Mt. Bianshi (Bianshishan), Maowen, 2600 m, 23 August 1985, F. Li 823-1 (IMD); Weizhou, Wenchuan, 2 May 1959, Maowen Exped. 2046 (PE, CDBI); Miansi, Wenchuan, 1780 m, 12 April 2017, Y. M. He et al. 2017007 (JXCM); Fengyi, Maoxian, 1800 m, 13 April 2017, Y. M. He et al. 2017009 (JXCM). ENGLAND: cultivated at Blackthorn Nussery (from Maoxian, Ogisu 92020), W. T. Stearn (PE).

Figures

Figure 4. Geographical variation in flower colour patterns within E. leptorrhizum (boxes), E. pauciflorum (circles), E. mikinorii (diamonds) and E. glandulosopilosum (triangle). The colour of the boxes, circles, diamonds and triangle represent flower colour. The population codes are shown in Table 1. The left area of the red dotted line is western China.

Figure 5. The variations and morphological characters of E. pauciflorum. A colour variations of inner sepals and petals B-D variations of the number and arrangement of stem-leaves E long creeping and thread-like rhizome.