Asarum koreanum J. Kim et C. Yook ex B. U. Oh 2020, sp. nov.
Creators: name: Oh, Ami
name: Leem, Hyosun
name: Oh, Byoung-Un
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Piperales
Aristolochiaceae
Asarum
Asarum koreanum

description: Asarum koreanum J. Kim et C. Yook ex B.U.Oh, sp. nov. (Figs. 1, 2, 3)
Type:— KOREA. Chungcheongbuk-do: Eumseong-gun, Mt. Gaseopsan, shady forest or forest edge in mountainous region, 563 m, 36°57’54” N, 127°42’03” E, 4 May 1997, B. U.Oh et al., 970504-1 (holotype CBU!, isotype CBU!).
Diagnosis:— Asarum koreanum is morphologically similar to A. sieboldii, but is distinguished by purple leaves, larger flowers, and deep purple calyx lobes with dense multicellular glandular trichomes (Table 1).
Perennial, 19.2–32.5 cm tall. Rhizomes creeping, ivory to whitish purple, 3.1–16.5 cm long, 1.4–4.4 mm in diam. Cataphylls entire, trichomes on margin, whitish purple, 2–4; first scale 8.5–15.6 mm long, 7.8–13.3 mm wide; second scale 5.0– 9.8 mm long, 6.0– 9.7 mm wide. Leaves alternate, simple, paired in an individual with flower; petiole slightly haired, whitish purple to purple, 14.1–21.4 cm long, 1.4–2.8 mm in diam.; leaf blade cordate or ovate-cordate, apex acute or acuminate, margin entire, base cordate, 6.4–16.7 cm long, 5.5–15.2 cm wide; adaxial surface pubescent, with short hairs, purple to purplish green or green, purple to yellowish green on vein, variegation not observed; abaxial surface short haired on vein, purple or pale green. Inflorescence solitary; peduncle glabrous, purple or whitish purple, 9.4–11.5 cm long, 0.3–2.4 mm in diam. Flowers actinomorphic; calyx tube campanulate or cup-shaped, 12.3–14.7 mm long, 13.4–14.9 mm in diam.; outer surface pale brown; inner surface vertical ridge, purple; calyx lobes 3, deltoid and undulate, apex acuminate or cuspidate, not recurved, dark purple, 8.8–17.8 mm long, 9.6–15.3 mm wide; stamens 12; filaments slightly flattened, whitish purple, 2.7–3.1 mm long, 0.6–0.7 mm wide; anthers extrorse, oblong, yellow, 1.6–1.8 mm long; ovary superior, placentation axilary, locules 6; styles radial, purple, 0.9–1.3 mm long, protuberance 1.3–1.6 mm tall, 1.5–1.9 mm long; stigmas lateral, roundish and convex. Fruits a fleshy capsule, irregularly dehiscent when ripe. Seeds numerous, slightly curved, light brown, with whitish brown appendage, 3.3–3.8 mm long, 1.8–2.0 mm in diam.
Distribution and habitat:—The distribution of A. koreanum is restricted to the central region of Korea (Chungcheongbuk-do), including Mt. Gaseopsan, Mt. Gunjasan, Mt. Baegaksan, Mt. Wolaksan, Mt. Songnisan, Mt. Samtaesan, and Mt. Yongsanbong. The populations were found in shady forest or forest edge.
Phenology:—Flowering is observed from April to June, and fruiting from June to August.
Chromosome number:— Asarum koreanum has 2 n =26 chromosomes.
Additional specimens examined: — KOREA. Chungcheongbuk-do: Danyang-gun Samtaesan, 20 April 2012, K. O.Yoo et al., 86066 (KWNU!); Danyang-gun Yongsanbong, 19 April 2012, K. O.Yoo et al., 85240 (KWNU!); Boeun-gun Songnisan, 21 May 2005, K. O.Yoo et al., 74821 (KWNU!).
Specimens examined for Asarum sieboldii: — KOREA. Chungcheongbuk-do: Boeun-gun Gubyeongsan, 25 May 2013, B. U. Oh et al., Boeun-gun (gubyeongsan)-130525-317 (CBU!). Jeollanam-do: Gurye-gun Imgeollyeong, 29 May 2010, B. U. Oh et al., 100529-imgeollyeong-002 (CBU!); the same locality, 29 May 2010, B. U. Oh et al., 100529-imgeollyeong-011 (CBU!); the same locality, 29 May 2010, B. U. Oh et al., 100529-imgeollyeong-024 (CBU!). Gyeongsangbuk-do: Sangju-si Jungbeol-ri, 25 May 2013, B. U. Oh et al., Sangju-si (baekbaegaksan)-130525-108 (CBU!); the same locality, 25 May 2013, B. U. Oh et al., Sangju-si (baekbaegaksan)-130525-112 (CBU!); the same locality, 25 May 2013, B. U. Oh et al., Sangju-si (baekbaegaksan)-130525-121 (CBU!).
description: Published as part of Oh, Ami, Leem, Hyosun & Oh, Byoung-Un, 2020, Asarum koreanum (Aristolochiaceae), a new species from Korea, pp. 173-178 in Phytotaxa 429 (2) on pages 174-177, DOI: 10.11646/phytotaxa.429.2.8, http://zenodo.org/record/13876785