Epimedium mikinorii Stearn, Kew Bull. 53: 214. 1998

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 : 46-48

4. Epimedium mikinorii Stearn, Kew Bull. 53: 214. 1998 Fig. 6

Type.

CHINA. Hubei: Enshi, 670 m, April 1995, Ogisu 95039, cultivated at Blackthorn Nursery, Kilmeston, Hampshire; collected by W.T.Stearn, 5 April 1997 (holotype: K, not seem).

Description.

Herbs 26-94 cm tall. Rhizome compact. Leaves basal and cauline, trifoliolate; leaflets adaxially dark green, lanceolate, 8-17.4 × 3-8.6 cm, leathery, abaxially glaucous, glabrous or with appressed hairs, base cordate with equal lobes rounded, those of lateral leaflets oblique with outer lobe large and acute, inner lobe smaller and rounded, margin closely spinose-serrulate, apex long acuminate. Flowering stem with 2 opposite or occasionally 3-whorled trifoliolate leaves. Inflorescence compound, loose, 8 –50(– 85)-flowered, ca. 7-30 cm long, glabrous, with lower peduncles 3-5-flowered. Pedicel 1.0-1.5 cm long, glabrous. Flowers ca. 2.5-3.5 cm in diam. Outer sepals oblong, 4-6 × 2-4 mm; inner sepals yellowish, white, rose-tinged or rose, elliptic, 11-16 × 7-12 mm. Petals longer and much narrower than inner sepals, yellow, orange, purple or purple with yellow-edged lamina ca. 3.5 mm high; spur slightly curved or almost straight, subulate, elongated, 15-20 mm long. Stamens ca. 4 mm long; anthers yellow or green, ca. 3 mm long. Follicles oblong, 8-15 mm long; style rostriform. Seeds numerous.

Distribution and habitat.

Epimedium mikinorii is restricted to the mountains of Hubei (Enshi), Western of China, usually occurring at elevations ranging from 500 m to 1700 m (Fig. 4 ).

Phenology.

Epimedium mikinorii flowers from April to June, and fruits from May to June.

Taxonomical remarks.

The field investigation found extensive colour variations. The inner sepals have different colours, ranging from white, rose-tinged, purple-tinged, through to rose and pale purple. Petals also exhibited abundant colour variation, such as yellow, orange, purple, purple but laminae yellow-edged or yellow at both ends while purple in the middle. Although the specimens of E. mikinorii that can be referred to are very limited, the characters and the descriptions of some herbarium specimens were consistent with our observations. Some specimens from Enshi had yellow flowers (B. L. Guo & X. Z. Luo 89012) or the flower colour varied from pale yellow to pale purple and purple (B. L. Guo A29, B. L. Guo A50) or from yellow to orange and pale purple (B. L. Guo & J. J. Liu 0810).

According to our field investigation and the common garden experiment on two populations, parts of the spurs were almost straight, while most were slightly curved (Fig. 6 ). The petals, in fact, presented a continuous variation from much longer to slightly longer than the inner sepals (Fig. 6 ).

As far as the indumentum of leaves concerned, we observed that approximately 40% of the individuals from HBES (near its type locality) and some individuals from HBXT were with white appressed hairs abaxially. Moreover, all the previous descrip tions and specimens on the flowering stem of E. mikinorii were with 2 opposite trifoliolate leaves. However, 3-whorled trifoliolate was also observed in the HBES population (S. X. Liu et al. 2016017).

Additional specimens examined.

CHINA. Hubei: Baiguo, Enshi, 754 m, 21 April 2016, S. X. Liu et al. 2016017 (JXCM); Xiashuba, Baiguo, Enshi, 500 m, 4 May 1989, B. L. Guo & X. Z. Luo 89012 (IMD); Baiguo, Enshi, 852 m, 8 April 2004, B. L. Guo A29 (IMD); Jinlong, Dengta, Enshi, 1100 m, 22 April 1974, X. S. Zou 74001 (HIB); Dongliushui, Dengta, Enshi, 900 m, 25 April 1974, X. S. Zou 74006 (HIB); Xintang, Enshi, 1100 m, 5 December 2004, Y. J. Zhang & X. D. Li 011 (HIB); Baiguoping, Enshi, 970 m, 5 December 2004, Y. J. Zhang & X. D. Li 017 (HIB); Xintang, Enshi, 985 m, 6 December 2004, Y. J. Zhang & X. D. Li 019 (HIB); Xintang, Enshi, 2 June 1974, Y. J. Ma 277 (HIB); Huangjindong, Xianfeng, 829 m, 7 April 2004, B. L. Guo A48 (IMD); Longfeng, Enshi, 533 m, 8 April 2004, B. L. Guo A50 (IMD); Changlinggang, Shaunghe, Enshi, 1700 m, 20 August 2005, B. L. Guo 05118 (IMD); Luzhuba, Baiyangping, Enshi, 635 m, 9 April 2008, B. L. Guo & J. J. Liu 0807 (IMD); Shaziba, Sancha, Enshi, 944 m, 12 April 2008, B. L. Guo & J. J. Liu 0809 (IMD); Changlinggang, Enshi, 1677 m, 13 April 2008, B. L. Guo & J. J. Liu 0810 (IMD).

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 6. The variations and morphological characters of E. mikinorii. A colour variations of inner sepals B colour variations of petals C individuals that with different flower colour.