Cardamine hunanensis Al

Wu, Lie, Liu, W. J., Mu, C. & Al-Shehbaz, Ihsan A., 2021, Cardamine hunanensis (Brassicaceae), a remarkable new species from Hunan (China) with fully bracteate racemes, Phytotaxa 512 (1), pp. 79-82 : 79-82

Cardamine hunanensis Al –Shehbaz, L.Wu & W.J.Liu, sp. nov.

Diagnosis:— Cardamine hunanens is is easily distinguished from the related C. lihengiana by having 3- or 5-foliolate (vs. simple) basal and lowermost cauline leaves and purple to violet (vs. white) petals 5–7 (vs. 3.5–4.5) mm long.

Type:— CHINA. Hunan: Yizhang, Mangshan Nature National Reserve , alt. 1280 m, 27 April 2020, W. J. Liu & X. F. Song ms724 (holotype, CSFI 076072 ; isotype, CSFI). Figures 1, 2 .

Description: —Plants perennial herbs, glabrous throughout, not glaucous. Rhizomes slender, not stoloniferous. Stems 25–40 cm tall, branched from base, simple or few branched above, erect to ascending, slender, angled. Basal and lowermost cauline leaves 3–5-foliolate; petiole 0.6–2 cm long, expanded at base, gradually reduced in length upwards; terminal leaflet reniform to suborbicular, 1.3–2 × 1.5–2.4 cm, palmately veined, base strongly cordate, margin with 5–7 shallow lobes or crenate, apex retuse; lateral leaflets with petiolules 1–4 mm long, blade broadly ovate-deltoid to ovate, distinctly smaller than terminal lobe, proximal pair smallest; middle and upper cauline leaves with axillary flowers, trifoliolate and short petiolulate, progressively smaller and becoming simple upwards; terminal leaflet reniform, shallowly 5-lobed; lateral leaflets ovate, sessile. Racemes bracteate throughout, lax in flower, much elongated in fruit; rachis straight; fruiting pedicels 0.5–1.5 cm long, ascending. Sepals oblong to oblong-ovate, 2.4–2.8 mm long, margin membranous; petals purple to violet with darker veins, obovate, 5–7 × 3–4 mm, apex rounded, abruptly narrowed at base to a short claw; median filament pairs 3.2–3.5 mm long, lateral pair ca. 3 mm long; anthers oblong, ca. 0.9 mm long. Fruits linear, young ones 2–2.5 cm × 1–1.5 mm; style 4–5 mm long. Mature seeds not seen.

Phenology: — Flowering in April into May. Distribution: —Known only from the type locality in Mangshan Nature National Reserve. Etymology: — The species is named after Hunan Province. Habitat : — Among shrubs in woody areas. The new species is accompanied mainly by tree plants of Cinnamomum

Schaeff. ( Lauraceae ), Schima Reinw. ex Blume ( Theaceae ) and Castanopsis Spach ( Fagaceae ); shrubs of Eurya Thunb.

( Theaceae ), Symplocos Jacq. ( Symplocaceae ), Maesa Forssk. ( Myrsinaceae ) and Lasianthus Jack ( Rubiaceae ); herbs of

Sarcopyramis Wall. ( Melastomataceae ), Zingiber Boehm. ( Zingiberaceae ) and Carex L. ( Cyperaceae ).

Discussion: — Cardamine hunanensis , which is known thus far only from Yizhang Xian (Hunan Province), most closely resembles C. lihengiana of Yiliang Xian (Yunnan), and the two xians (counties) are separated by a distance of some 1,385 km. From the latter, C. hunanensis is readily distinguished by being non-stoloniferous and by having 3–5-foliolate basal and lowermost cauline leaves; purple to violet petals 5–7 × 3–4 mm, fruiting pedicels 0.5–1.5 cm long, sepals 2.4–2.8 mm long, and styles 4–5 mm long. By contrast, C. lihengiana is stoloniferous with simple basal and lowermost cauline leaves, white petals 3.5–4.5 × 1.5–2 mm, fruiting pedicels 1.5–3 cm long, sepals 1.5–1.8 mm long, and styles 1–2 mm long.