Description
Herbs, perennial, seasonally dormant. Roots contractile, string-like, 1.6–5.3 mm in diam. Rhizome hypogenous, erect, 10–27 mm in diameter. Leaves in a rosette, appearing after flowers, 2–5; petiole basally sheathing, sulcate, purplish striped, 5.8–17 cm × 1.9–10.2 mm; leaf blade subcordate or cordate-ovate, 7–24 × 4.6–19 cm, yellowish green or green, base cordate or reniform, slightly uneven, margin entire, apex acute, acuminate, or obtuse; venation reticulate, midvein prominent, primary lateral veins 5–7 on each side of midvein, arching and branching apically, merging with inconspicuous marginal veins, lowermost veins running into basal lobes. Inflorescences 1–3, in a sympodium, appearing before leaves, 29–62 flowered; peduncle erect, partly below ground, shortly exserted above ground, terete, 3.5–21 cm × 0.3–2.1 mm, yellowish green or purplish tinged. Spathe hood-like, convolute at base, fleshy, 6–11 × 2.8–5.8 cm, yellowish brown or yellowish green, usually dark purple spotted or striped, apex 2-keeled, acute or acuminate, twisted or incurved, not persisting in fruit. Spadix subglobose or ellipsoid, 9.3–17 × 7.4–15 mm, stipitate; stipe cylindrical, 2–9.3 × 2–4.4 mm. Flowers bisexual, 2.7–5.5 × 2.3–5 mm; tepals 4, imbricate, yellow; stamens 4, free; filaments flattened, connective slender; anthers 2-locular, basifixed, yellow, dehiscing longitudinally; ovary 1-locular; ovule 1; style cylindrical, truncate or capitate. Infructescence globose or broadly ellipsoid, spadix 2.7–3.3 × 2.4–3 cm, stipe 10.8–19 × 4.5–6.3 mm. Fruit a berry, embedded in enlarged spongy spadix, initially greenish or dark purple, becoming blackish brown at maturity, ripening below ground in summer of same year. Seed brown, somewhat irregular in shape, 4.6–11.5 × 4.8–13.7 mm, smooth. Chromosome number: 2n = 30.
Distribution
Symplocarpus koreanus is restricted to the Korean Peninsula (North Korea, including Hamgyeongnam-do and South Korea, including Gyeonggi-do, Gangwon-do, Chungcheongbuk-do, Jeollabuk-do, Gyeongsangbuk-do, and Gyeongsangnam-do). It typically occurs in shaded, wet places, along streams and on moist rocky hillsides in mixed deciduous forests from ca. 100 to 750 m elevation.
Note
Symplocarpus koreanus has long been considered to be conspecific with S. renifolius in Japan. A recent phylogenetic study based on extensive sampling revealed that S. renifolius in Korea, now described as S. koreanus, is more closely related to S. nipponicus in Korea and Japan than it is to S. renifolius in Japan and the Russian Far East (Lee et al., 2019).
Morphologically, S. koreanus is most similar to S. renifolius in Japan, including in life history traits, perhaps sharing their most recent common ancestor. However, S. koreanus has a much smaller and more spherical spadix with fewer, smaller flowers than S. renifolius. The average spadix length of S. koreanus is 12 mm, while that of S. renifolius is 22 mm. In addition, the average spadix width of S. koreanus is 10 mm, whereas that of S. renifolius is 15 mm. The ratio between spadix length (L) and width (W) is also different: 1.2 and 1.4 for S. koreanus and S. renifolius, respectively. Lastly, S. koreanus has many fewer flowers per spadix than S. renifolius: average of 40 versus 79. Thus, the spadix of S. koreanus in its size, shape and flower number is more similar to the spadix of S. nipponicus than to S. renifolius.
Reference
Symplocarpus koreanus (Araceae; Orontioideae), a new species based on morphological and molecular data
Joon Seon LEE, Seon-Hee KIM, Yongsung KIM, Youl KWON, JiYoung YANG, Myong-Suk CHO, Hye-Been KIM, Sangryong LEE, Masayuki MAKI, Seung-Chul KIM
Korean J. Pl. Taxon. 2021;51(1):1-9. Published online March 31, 2021
DOI: https://doi.org/10.11110/kjpt.2021.51.1.1
식물자원
국가생물종지식정보시스템 > 
