NOVON 10(3): 209-214. 2000.

New Taxa and Combinations in Eleutherococcus (Araliaceae) from Eastern Asia

Kim, Chul Hwan and Byung-Yun Sun

Faculty of Biological Sciences, Chonbuk National University, Chonju, Chonbuk 561-756, Korea

Abstract. While preparing a monographic study of Eleutherococcus, we discovered the three new taxa, E. brachypus var. omeiensis, E. huangshanensis, and E. pseudosetulosus, described here. In addition, three new combinations, E. divaricatus var. chiisanensis, E. pilosulus, and E. pubescens, are proposed.

Eleutherococcus Maximowicz (1859, emend. C. H. Kim & B.-Y. Sun) is an endemic Asian genus with about 35 species distributed mainly in northeastern Asia including China, Korea, and Japan, with some members also extending to southwestern Asia (Kim, 1997). The genus Acanthopanax (Decaisne & Planchon) Witte was initially recognized as a subgenus of Panax L. by Decaisne and Planchon (1854) and raised to generic rank by Witte (1861). Harms (1894) combined the two genera, and adopted the name Acanthopanax, which has since been widely used by many botanists. However, Acanthopanax does not have priority and is therefore illegitimate under current ICBN nomenclature (Greuter et al., 1994),. Some recent authors (e.g., Hu, 1980; Ohashi, 1987; Hsu & Pan, 1993) have therefore transferred taxa from Acanthopanax to Eleutherococcus.

Plants of Eleutherococcus are shrubs and are characterized by the presence of prickles, five-merous flowers with two to five carpels, and palmately compound leaves. The genus as a whole is highly variable resulting in much taxonomic confusion (Kim, 1997). For example, E. koreanus Nakai was distinguished from E. senticosus (Ruprecht & Maximowicz) Maximowicz based on its unarmed twigs. However, examination of specimens from various regions , has shown this character to be merely included within the limits of natural variation among individuals. While preparing a monographic study of Eleutherococcus, we found three new taxa and describe them here: E. brachypus var. omeiensis, E. huangshanensis, and E. pseudosetulosus; three new combinations are also made: , E. divaricatus var. chiisanensis, E. pilosulus, and E. pubescens.

Foliola 3, terminalia foliola elliptica, glabra; terminales petioluli ca. 1 cm longi, glabri. Flores cum pedicellis articulatis.

A hermaphroditic shrub to 2 m tall; stems erect, glabrous. Leaves 3-foliolate, leaflets elliptic, somewhat chartaceous, glabrous on both surfaces, secondary veins 3-- to 5 pairs, the apex obtuse or acuminate, the margin entire, the base cuneate; petiole 0.5 cm long, glabrous; terminal leaflets 2--4 H 1--1.5 cm, petiolule relatively long, ca. 1 cm; lateral leaflets somewhat smaller than terminal ones, sessile or short-petiolulate. Inflorescence of umbels arranged in a simple cyme at the end of long branches of the current year's growth, rarely at the end of short branches, glabrous; pedicel articulated at uppermost part, 1--1.5 cm long, glabrous. Calyx 5-toothed; petals 5; stamens 5; carpels 5, style united into a single column, stigma indistinctly 5-lobed, ca. 1 mm long; ovary 2 mm long. Fruit unknown.

This variety is thus far known only from Mt. Omei, Sichuan, China, from which the epithet was derived. The typic variety occurs in Gansu, Shanxi, and Shaanxi in China. Eleutherococcus brachypus var. omeiensis differs from other members of the genus by its articulation in the uppermost part of the pedicel. This variety is also distinguished from the typic variety in having a long (ca. 1 cm) petiolule on the terminal leaflet. Other features are the same and hence we recognize it as a variety of E. brachypus.

Eleutherococcus divaricatus var. chiisanensis differs from the typic variety in having setose trichomes on its abaxial leaf surface rather than exclusively sericeous indumentum. In variety chiisanensis, these setose trichomes are often mixed with sericeous ones in varying degrees. Other morphological features are the same, and hence we recognize this taxon as a variety of E. divaricatus. It is endemic to the Korean peninsula, whereas the typic variety occurs in Hokkaido, Honshu, Shikoku, and Kyushu in Japan and Shanxi, Henan, and Zhejiang in eastern China. Among the syntypes (E. Taquet 890, E. Taquet 889, E. Taquet 5660, and T. Nakai 369), the first, here selected as the lectotype, has relatively well--preserved leaf indumentum and distinct pedicels in umbels, which are diagnostic characters.

Representative specimens. KOREA. Cheju-do: in silvis Yongsil 1000 m, 17 Aug. 1918, E. Taquet 889 (A, C, E, TI); in silvis Yongsil 1000 m, E. Taquet 5660 (E); Yongshil 1100 m hill, 18 Sep. 1995, B. Y. Sun s.n. (JNU [5 sheets]). Chollabuk-do: Mt. Unjang, 6 Aug. 1994, C. H. Kim 5044 (JNU [8 sheets]). Chollanam-do: Mt. Chiri, 1 July 1913, T. Nakai 369 (TI); Chirisan (Mt. Chiri), Aug. 1934, R. K. Smith s.n. (US); Mt. Chiri, Nogodan, 11 Aug. 1988, C. H. Kim 5011 (JNU [8 sheets]). Hamgyungbuk-do: Myungchon-gun, Sanggo-myon, Chilbosan, 19 Aug. 1924, ? 114 (TI). Hamgyungnam-do: Sam-su District, Onkol-muri valley, 8 Aug. 1887, V. Komarov 1148 (BM); Hogen, yutenji, Hongo-san, 7 July 1918, E. H. Wilson 10494 (A). Kangwon-do: Mt. Odae, 17 Aug. 1988, C. H. Kim 5042 (JNU [2 sheets]); Inje-gun, Daeamsan, 28 Sep. 1969, Y. M. Kang 44755 (SNU); Daekwalyung, Neugchongsan, 22 Aug. 1969, T. B. Lee & M. Y. Cho s.n. (SNUA). Kyungsangbuk-do: without precise locality, 13 Sep. 1938, T. H. Chung 9556 (SNU).

Frutex erectus; ramulis glabris; internodio sparsis triangulis non-elasticis aculeis, ca. 0.5 cm longis, ca. 0.2 cm latis; foliola 5, supra et subtus glabra, duplicato-serrata. Umbellae (inflorescentiae) glabres.

A hermaphroditic shrub to 5 m tall; stems erect, glabrous with scattered prickles, sometimes a single prickle at a node or below the petiole. Prickles non-elastic and stout, 0.5 cm long, 0.2 cm wide, sharp-pointed with a broadened and enlarged base, pointing downward; the base narrowly elliptic, 1 cm long. Leaves 5-foliolate, blade widely elliptic or ovate, ca. 10 H 5 cm, chartaceous, glabrous on both surfaces, lateral veins 7-- to 9 pairs, the apex acute to acuminate, the margin doubly serrate, the base cuneate; petiolule of terminal leaflet 0.5 cm long, glabrous; petiole ca. 8 cm long, glabrous. Inflorescence of umbels arranged in a simple cyme at the end of long branches of the current year's growth, glabrous; pedicel 1 cm long, glabrous. Calyx dentate or obscure; petals 5; stamens 5, the filament 2.5 mm long; carpels 5 or 3 to --4, styles united into a single column, stigma indistinctly 5-lobed, sometimes 3- to --4-lobed, 1.5 mm long; ovary 2 mm long. Fruits globose, 5-angular when young, 8 mm long; the disc ca. 3 mm wide. Flowering August, fruiting October.

This species is restricted to Mt. Hwangshan, Anhui, China, at around 2000 m elevation and is named for the type locality. Eleutherococcus huangshanensis is most similar to E. henryi Oliver, E. leucorrhizus Oliver, and E. setchuenensis (Harms) Nakai. However, it differs from E. henryi by the glabrous nature of its inflorescence, twig, and abaxial leaf surfaces, and from E. setchuenensis by its chartaceous leaves with 5 leaflets and double serrate margins. This species is also distinguished from E. leucorrhizus by the shape, position, and number of prickles on its twigs. Characteristics of the prickles and also constancy in the number, shape, and pubescence of plant parts are usually important diagnostic features for evaluating species limits throughout the genus, and thus E. huangshanensis is sufficiently well distinguished from its allied species to be recognized as distinct. The three related species are distributed widely in China. However, E. leucorrhizus occurs in central and western China including Sichuan, Yunnan, Hubei, Gansu, and Shaanxi, and extending to Bhutan; E. setchuenensis is mainly found in central China; and E. henryi is distributed in central middle and eastern China centering on Hubei.

Paratypes. CHINA. Anhui: Wang Shan, 1800 m, 28 Aug. 1923, N. K. Ip s.n. (UC); Hwang Shan, 1900 m, 11 Aug. 1924, K. Ling 1172 (UC); Wang Shan, 23 Sep. 1965, ? 779 (PE); Wang Shan, 1800 m, 14 Aug. 1973, Zhou 474 (PE); Shexian, 18 Sep. 1987, C. L. Huang 0253 (AAUF).

This species has previously been recognized as a variety of either E. giraldii or E. wilsonii. Comparison of these three taxa, however, shows that E. pilosulus has narrower leaflets, a densely pubescent abaxial leaf surface, and twigs with elastic prickles with an elliptically protuberant base. whereas Eleutherococcus. giraldii has glabrous leaflets and twigs with elastic prickles with an indistinct base, and E. wilsonii has glabrous leaflets and almost unarmed twigs. Eleutherococcus pilosulus is limited to northern China, including Gansu and Qinghai, whereas E. wilsonii is distributed widely in China except the eastern part, and E. giraldii mainly occurs in Gansu, Hubei, and Shanxi, Shaanxi of upper middle China. On the basis of these characters, we, therefore, prefer to recognize E. pilosulus as a distinct species.

Representative specimens. CHINA. Gansu (Kansu): Hsia Mo K'ou, near Lichen, 2000--2300 m, 7 July 1923, R. C. Ching 337 (A, US); Taochow, SW of Tow river, Wm. Purdom s.n. (A); Tao river basin, W of Adjuan, eastern Minshan range, 3050 m, 5 July 1925, J. F. Rock 12657 (A, C); Tianzhu, 2500 m, 14 July 1959, He 4834 (PE). Qinghai: Menyuan, 2500 m, 19 June 1960, Qinghai-Gansu Exped. 2687 (PE).

Frutex scandens; ramus internodio aliquantum setis densis, ca. 0.25 cm longis, aliquantum triangulis aculeis raris, ca. 0.4 cm longis, ca. 0.15 cm latis, nodi vel petioli basis absque aculeo. Pedunculi 17--42 mm, glabri; pedicelli 8--10 mm, glabri.

A dioecious shrub to 2 m tall; stems scandent, " densely hirsute, trichomes slender and somewhat flexuous, 0.25 cm long, a few scattered prickles, prickles absent at node or below the petiole. Prickles pointing downward, broadened at base, 0.4 cm long, 0.15 cm wide. Leaves 5-foliolate; terminal leaflet obovate, 3.8--4.4 X 1.7--2 cm, slightly setose on adaxial surface, glabrous on abaxial surface, lateral veins 5 to --6 pairs, the apex acuminate, the margin doubly serrate, the base cuneate; petiolule of terminal leaflet 0--3 mm long; petiole 5.2--6.2 cm long, glabrous. Inflorescence a solitary umbel at the end of short branches of current year's growth; peduncle 1.7-4.2 cm long, glabrous; pedicel 0.8-1 cm long, glabrous. Calyx minutely 5-dentate; carpels 5, styles 5, connate to above middle, free arms recurved. Fruits widely globose, 6--7 mm long, black, 5-angular when young; the disc 1 mm wide. Fruiting September.

This species is restricted to Sichuan Province, China. The name is derived from the nature of the surface of its twigs, which resembles that of E. setulosus (Franchet) S. Y. Hu. Eleutherococcus setulosus and the new species described here are readily distinguishable from other members of the genus by their bristle-like elastic prickles at the internodes along the twigs. However, E. pseudosetulosus differs from E. setulosus by its glabrous peduncle and pedicel, longer and sparser bristle-like prickles in the internodes, and the absence of nonelastic recurved prickles at the nodes. Eleutherococcus setulosus also occurs in Sichuan Province.

This species is similar to E. gracilistylus and E. spinosus, but differs from them in having sericeous hairs throughout the abaxial leaf surface rather than being glabrous except with tufted hairs in the axil of the veins and setose trichomes along the midvein. These characteristics are constant throughout the species. Eleutherococcus spinosus is confined to the Japanese archipelagos, whereas E. gracilistylus is distributed throughout China and on Cheju Island in Korea. Based on these differences, we prefer to recognize E. pubescens as a distinct species.

Representative specimens. CHINA. Hubei (Hupeh): Fan-sien, ca. 800 m, 20 May--3 June 1906, C. Cilvestris 1598 (A[photo]); Wuchang, 23 Apr. 1933, S. C. Sun 1055, 1075 (A); Tung Chien Hsien, road side, 10 Aug. 1928, H. G. Cheo 183 (NY); Enshi, 1400 m, 22 June 1958, ? 24397 (NAS, PE); Yichang, 700--800 m, 7 May 1963, Z. D. Jiang 61 (PE). Henan (Honan): without precise locality, ? 20181 (PE). Jiangsu (Kiangsu): Nanking, 19 May 1921, L. F. Tsu 591 (UC). Shanxi (Shansi): Yuan Kiu Hsien, Ni Shan, 28 Sep. 1921, Y. Hers H-1824 (A). Sichuan (Szechuan): Le-po Hsien, 2800 m, 14 July 1934, T. T. Yu 3391 (PE).

Acknowledgments. This work was supported by the Korea Science and Engineering Foundation (grant no. KOSEF 951-0506-040-2) to B.-Y. Sun. The authors thank Pete Lowry and two anonymous reviews for their helpful comments on this manuscript and the directors of the following herbaria for the loan of specimens: A, AAUF, ANSP, B, BM, C, E, FI, IBK, K, KUN, KYO, L, LINN, MAK, MHA, MO, NAS, NY, P, PE, PNH, S, SING, SNU, SNUA, TI, U, UC.

Literature Cited