Epimedium longnanense Y.J.Zhang, 2023

Jiang, Jianhang, Ji, Ying, Li, Jianqiang & Zhang, Yanjun, 2023, Epimedium longnanense (Berberidaceae), a new species from Gansu, China, PhytoKeys 219, pp. 97-106 : 97

Epimedium longnanense Y.J.Zhang sp. nov.

Figs 1 , 2

Type.

China, Gansu, Longnan Prefecture, Kangxian County, Kangnan Forest District , 32°59'N, 105°38'E, alt. 2000 m, 15 June 2022, Yanjun Zhang 709 (holotype, HIB!; isotypes, HIB!) .

Diagnosis.

Epimedium longnanense is closely similar to E. flavum Stearn in morphology, but can be easily distinguished by its elongated rhizome, trifoliolate leaves, and relatively smaller and pale pink or purplish-red inner sepals.

Description.

Perennial herbs 15-20 cm tall. Rhizome ca. 15 cm or longer, ca. 1 mm in diam., elongated. Leaves basal and cauline, trifoliolate. Leaflets 2.4-4 × 2.3-4 cm, broadly ovate or almost orbicular, membranous, adaxially glabrous, abaxially sparsely pubescent, base deeply cordate with usually rounded lobes, those of lateral leaflets unequal, margins spinous-serrulate, apex usually acute or obtuse. Flowering stem with one leaf, or occasionally two alternate leaves, glabrous. Inflorescence compound or simple, 5-15-flowered, 10-15 cm long, glandular, pedicels 1.5-3.5 cm long. Flowers 3-5 cm in diam., yellow. Outer sepals ovate, soon falling; inner sepals 6-8 × 2-3 mm, narrowly ovate, pale pink or purplish-red. Petals 1.5-2.5 cm, much longer than inner sepals, horn-shaped, yellow, spurs slender; basal lamina 6-8 mm high, distinct. Stamens ca. 4 mm long, included, anthers ca. 3 mm long, anthers and pollen pale yellow. Capsules ca. 2 cm long.

Phenology.

Flowering in June; fruiting in late June and early July.

Etymology.

Longnan is located in the southeast of Gansu Province, the intersection of Qinba Mountain, Loess Plateau and Qinghai Tibet Plateau in China. Longnan is a biodiversity hotspot where many new species or new species records have been found ( Liu et al. 2018; Qin et al. 2020; Zhang et al. 2022a). The new species, E. longnanense , is found in this region and is named after the geographic name.

Distribution and habit.

At present, Epimedium longnanense is only known from its type locality, i.e. Kangnan Forest District, Kangxian County, Longnan Prefecture, Gansu Province, China. The new species mainly occurs in thickets at elevations of 1800-2300 m and is usually together with Fargesia nitida (Mitford) Keng f. ex Yi, Rubia cordifolia L., Smilax stans Maxim., Cardamine tangutorum O. E. Schulz and Veratrum nigrum L. It often grows in stone crevices with barren soil, and its elongated and slender rhizome might be an adaptive characteristic of its living environment. Except for E. longnanense , there are two other species of Epimedium , E. brevicornu Maxim. and E. pubescens Maxim., in Gansu Province, China. In the type locality of E. longnanense , we also found E. pubescens at elevations of 300-1500 m, but no sympatric distribution of these two species was found.

Chinese name.

Long nan yin yang huo (陇南淫羊藿).

Additional specimens examined (Paratypes).

China, Gansu Province, Longnan Prefecture, Kangxian County, Kangnan Forest District , alt. 2270 m, 20 June 2021, Yanjun Zhang 699 (HIB!); loc. cit., alt. 1900 m, 30 June 2022, Yanjun Zhang 710 (HIB!) .

IUCN Red list category.

Data available for the new species are still insufficient to assess its conservation status. According to the IUCN criteria ( IUCN 2022), it is considered Data Deficient (DD) until more information becomes available. Although E. longnanense currently has relatively good growth and protection status, we would like to elaborate that many other species of Epimedium have severely suffered from destructive excavation due to their huge medicinal values. Therefore, special attention should be given to the conservation of the new species of Epimedium .

Figures

Figure 1. Epimedium longnanense A plant B flower C petal D inner sepal E stamen and gynoecium. Drawn by Nan Jia.

Figure 2. Epimedium longnanense A habitat B plant C leaves (abaxial sides) D simple inflorescence with a flowering stem bearing one leaf E compound inflorescence with a flowering stem bearing two alternative leaves F flowers (adaxial view) G flower (abaxial view) H flower (Side view) I flower (Side view) and immature capsules J mature capsules K rhizome. Photographed by Yanjun Zhang and Ying Ji.