A new distribution record of Trichosanthes cucumeroides (Ser.) Maxim. ex Franch. & Sav. (Cucurbitaceae) in Korea

Article information

Korean J. Pl. Taxon. 2020;50(3):356-360
Publication date (electronic) : 2020 September 30
doi : https://doi.org/10.11110/kjpt.2020.50.3.356
Plant Resources Division, National Institute of Biological Resources, Incheon 22689, Korea
1Woori Botanical Garden, Gwangju 61431, Korea
*Author for correspondence: foko@korea.kr
Received 2020 July 6; Revised 2020 August 5; Accepted 2020 September 15.

Abstract

A new distribution of Trichosanthes cucumeroides (Ser.) Maxim. ex Franch. & Sav. is discovered in Korea. This species was collected from forest margins on Ando Island, Ando-ri, Nam-myeon, Yeosu-si, in Jeollanam-do. T. cucumeroides is clearly distinguished from other species of the genus by having three- or five-lobed leaf blades, linear-lanceolate and minute bracts with entire margins, and oblong to triangular-ovoid seeds. Here, we provide precise description, a taxonomic key to the Korean Trichosanthes species, illustrations, and photographs of its habitat. The Korean name for the species is established as ‘Bul-geun-ha-neul-ta-ri’ considering the reddish color of its fruit.

Trichosanthes L. (Cucurbitaceae) contains approximately 100 species which are distributed in southern to eastern Asia including India, Sri Lanka, China, Malesia, Philippines, Taiwan, Japan, and Australia (Rugaya and de Wilde, 1997, 1999; Cooper and de Boer, 2011; de Boer and Thulin, 2012). Within Trichosanthes, six groups had been recognized as sections on the basis of morphological characteristics; fruit, seed, leaves, bracts of staminate inflorescences, probracts of pistillate inflorescences (Rugayah and de Wilde, 1999; Cooper and de Boer, 2011). Recently, molecular data have suggested the infrageneric classification of the genus Trichosanthes with two subgenera [subgn. Trichosanthes, subgn. Scotanthus (Kurz) H. J. de Boer] 11 sections (sect. Asterospermae W. J. de Wilde & Duyfjes, sect. Cucumeroides (Gaertn.) Kitam., sect. Edulis Rugayah, sect. Foliobracteola C. Y. Cheng & C. H. Yueh, sect. Gymnopetalum (Arn.) H. J. de Boer, sect. Involucraria (Ser.) Wight, sect. Pseudovariifera H. J. de Boer, sect. Villosae (Yueh & L. Q. Huang) H. J. de Boer, sect. Trichosanthes, sect. Tripodanthera (M. Roem.) H. J. de Boer, and sect. Truncata C. Y. Cheng & C. H. Yueh (de Boer and Thulin, 2012; de Boer et al., 2012).

Trichosanthes cucumeroides (Ser.) Maxim. ex Franch. & Sav. belongs to subgn. Trichosanthes sect. Cucumeroides. The sect. Cucumeroides comprises ca. 10 species that are mainly distributed in Australia, Southeast Asia, and China (Cooper and de Boer, 2011). Species in sect. Cucumeroides are distinct from the other sections by their ovaries with 3 locules together with inflorescences without probracts, white fruits becoming reddish when they are matured, and gray or brown turgid seeds with coarsely undulate margins (Rugayah and de Wilde, 1999; de Wilde and Duyfjes, 2004; Cooper and de Boer, 2011). T. cucumeroides, known as distributed in China, India, Japan, and Taiwan is distinct from the other species in sect. Cucumeroides with their 3- or 5-lobed leaf blades, linear-lanceolate and minute bracts with entire margins, and oblong to triangular-ovoid seeds (Huang et al., 2011).

In Korea, only two taxa in the genus Trichosanthes are reported; T. kirilowii Maxim. var. kirilowii and T. kirilowii var. japonica (Miq.) Kitam. (Kim and Choi, 2018), which are member of sect. Foliobracteola (de Boer and Thulin, 2012). T. kirilowii var. kirilowii is distributed in East Asia, and found southern part of Korea (Kim and Choi, 2018). On the other hand, T. kirilowii var. japonica is distributed in Korea and Japan, and found on southern islands area in Korea (Kim and Choi, 2018).

During the Plant Diversity Research on Jeollanam-do Province, an unrecorded species, T. cucumeroides was confirmed in the forest margins in Ando Island, Ando-ri, Nam-myeon, Yeosu-si in Korea. Here, we present the specific description, illustrations, taxonomic key to Korean Trichosanthes species as well as the photographs of its habit.

Taxonomic Treatment

Trichosanthes cucumeroides (Ser.) Maxim. ex Franch. & Sav., Enum. Pl. Jap. 1: 172, 1873 (Figs. 1, 2). Bryonia cucumeroides Ser. in DC., Prodr. 3: 308, 1828. Trichosanthes ovigera Blume subsp. cucumeroides (Ser.) C. Jeffrey, Mansfeld’s Encycl. 3: 1528 (6: 2825), 2001.—TYPE: JAPAN. “Patria ignotus, Seringe manuscript”, Walllich? (not seen).

Fig. 1.

Illustration of Trichosanthes cucumeroides. A. Habit (♂). B. Pistillate flower. C. Seed. D. Fruit.

Fig. 2.

Photographs of Trichosanthes cucumeroides in their habitat. A. Habit. B. Staminate flower. C. Pistillate flower. D. Staminate flower (side view). E. Leaf (adaxial surface). F. Leaf (abaxial surface). G. Fruit.

Korean name: Bul-geun-ha-neul-ta-ri (붉은하늘타리).

Herbs perennial, dioecious, climbing. Roots fasciculate, thickened. Stem slender, ca. 1.5 mm in diam., branched, longitudinally grooved, sparsely to densely pubescent with white short simple hairs. Leaves alternate, simple, petiolate; petiole (2–)4–8.5(−10) cm long, longitudinally grooved, densely pubescent with simple hairs intermixed with short conical stiff hairs; blade ovate, broadly ovate to triangular-ovate, shallowly 3- or 5-lobed, (5–)10–16(−19) × (5–)11–16(−18) cm, apex obtuse or acuminate, base cordate, margins slightly undulate, ciliolate, abaxial surface pale green, densely pubescent with short simple hairs, adaxial surface green to dark green, sparsely to densely pubescent with short simple hairs, especially along midvein; central lobe triangular to triangular-ovate, (3.5–)6–6.5 × (2.7–)7.3–10 cm; tendrils lateral, simple or bifid, spirally twisted; stipule absent. Inflorescences axillary, racemes or flowers solitary, pedunculate. Staminate inflorescences racemes, 6–10-flowered; peduncle 4–10 cm long, sparsely pubescent with short simple hairs; bracts linear-lanceolate, entire, minute, 1–3 mm long, densely pubescent with white short simple hairs; pedicel 5–8 mm long, sparsely to moderately pubescent with short simple hairs. Pistillate inflorescences flowers solitary; pedicel 0.5–1 cm long. Flowers: calyx tube salver-shaped, 6–7.5 cm long, outer surface densely pubescent with short simple hairs, sometimes glabrate, 5-lobed; calyx lobes green, linear-lanceolate to narrowly triangular, 2.5–4 mm long, less than 1 mm wide, abaxial surface densely pubescent with short simple hairs, adaxial surface sparsely pubescent with short simple hairs; corolla white; corolla tube 6–7.5 cm long, 5-lobed; corolla lobes oblong or oblong-elliptic, 1–2 × 0.4–0.7 cm, apex and margins long fimbriate, 4- or 5-veined; veins green; fimbriae elongate. Staminate flowers: stamens 3, short; anthers blackish, 1.5–2.5 mm long. Pistillate flower: ovary inferior, narrowly oblong, pubescent; placentae 3; ovules many; stigmas 3. Fruit berry, orange, orange-red or red, ellipsoid to globose, 5–7 × 3–5.5 cm, fleshy, smooth, apex beaked; fruiting pedicel ca. 1 cm long, pubescent. Seeds brown or dark brown, many, oblong to triangular-ovoid, 3-loculed, 0.6–1.2 × 0.7–1.4 cm, with 2 longitudinal bands, 2 lateral locules empty, rugulose.

Flowering: Jul to Sep.

Fruiting: Sep to Nov.

Distribution: China, India, Japan, Taiwan, and Korea.

Specimens examined: KOREA. Jeollanam-do: Yeosu-si, Nam-myeon, Ando-ri, Ando Isl., 34°28′49.33″N 127°48′43.35″E, elev. 10 m, 13 Oct 2018, Yang-Hoon Cho & Seok-Soon Kim WR-181013-001 (♀, 2 sheets [KB, NIBRVP0000772811]); same locality, 34°28′52.54″N 127°48′41.7″E, elev. 10 m, 5 Aug 2019, Yang-Hoon Cho & Seok-Soon Kim JN19167 (♂, 2 sheets [KB, NIBRVP0000772029]); same locality, 34°28′52.54″N 127°48′ 41.7″E, alt. 10 m, 16 Oct 2019, Yang-Hoon Cho & Seok-Soon Kim JN19253 (♀, [KB, NIBRVP0000772115]); same locality, 5 Aug 2019, Jin-Seok Kim kjs19033 (♂, 3 sheets [KB, NIBRVP0000772807]), kjs19034 (♀, 2 sheets [KB, NIBRVP0000772808]); same locality, 6 Oct 2019, Jin-Seok Kim kjs19035 (♀, 2 sheets [KB, NIBRVP0000772809]).

Note: Trichosanthes cucumeroides was known to be distributed in China, India, Japan, and Taiwan. From this study, the new natural distribution is discovered at forest edge in Ando Island, Ando-ri, Nam-myeon, Yeosu-si, Jeollanam-do, Korea. The population was composed of 20 individuals within 20 × 20 m2 in size. The upper vegetation was made up of Pinus thunbergii Parl., Celtis sinensis Pers., Broussonetia papyrifera (L.) L’Her. ex Vent, Camellia japonica L., Prunus spachiana (Lavallee ex Ed. Otto) Kitam. f. ascendens (Makino) Kitam., Picrasma quassioides (D. Don) Benn., and Mallotus japonicus (L. f.) Mull. Arg., etc. The low vegetation was made up of Dryopteris sacrosancta Koidz., Clematis apiifolia DC., Sinomenium acutum (Thunb.) Rehder & E. H. Wilson, Humulus japonicus Siebold & Zucc., Trichosanthes kirilowii Maxim. var. japonica (Miq.) Kitam., Rubus hirsutus Thunb., Pueraria lobata (Willd.) Ohwi, Orixa japonica Thunb., Hedera rhombea (Miq.) Bean, Phryma leptostachya L. var. oblongifolia (Koidz.) Honda, Ligustrum obtusifolium Siebold & Zucc. Melampyrum roseum Maxim. Artemisia indica Willd., Commelina communis L., Oplismenus undulatifolius (Ard.) Roem. & Schult., and Dioscorea quinqueloba Thunb.

Trichosanthe cucumeroides (Ser.) Maxim. ex Franch. & Sav. was first recognized on the basis of its horizontally oblong seeds baring longitudinal bands (de Candolle, 1828). It is most similar to T. pilosa Lour. in sect. Cucumeroides distributed in Southeast Asia including India, Indonesia, Nepal, Thailand, and Vietnam (Huang et al., 2011). However, T. cucumeroides is differ from T. pilosa in having linear-lanceolate (vs. lanceolate or oblanceolate) and much smaller (1–3 mm long vs. ca. 1.6 cm × 5–6 mm) bracts with entire margins (vs. dentate margins), and sparsely to densely pubescent adaxial surface of leaves (vs. glabrous or puberulent). Meanwhile, some authors have treated T. cucumeroides as synonym of T. pilosa (Cooper & de Boer, 2011).

In addition, T. cucumeroides is distinct from T. kirilowii var. kirilowii and var. japonica, which are distributed in Korea, by its minute, linear-lanceolate bracts with entire margins (vs. distinct, broadly ovate to obovate bracts with coarsely dentate margins), oblong (vs. obovate) corolla lobes with narrower in width (0.4–0.7 cm vs. about 1.8 cm), orange to red (vs. dull yellow to yellowish brown or orange) fruits when they are matured, and turgid, 3-loculed (vs. not turgid, 1-loculed) seeds.

Key to Korean Trichosanthes taxa

  • 1. Bracts minute, linear-lanceolate, 1–3 mm long, margins entire. Calyx lobes minute, 2.5–4 × ca. 1 mm. Corolla lobes oblong, 1–2 × 0.4–0.7 cm, margins long fimbriate to apex. Fruits orange to red. Seeds turgid, 3-loculed ・・・ ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ T. cucumeroides 붉은하늘타리

  • 1. Bracts distinct, broadly ovate to obovate, 15–30 mm long, margins coarsely dentate. Calyx lobes prominent, 8–15 mm long in staminate flowers, 35–40 mm long in pistillate flower. Corolla lobes obovate, ca. 2 × 1.8 cm, margins long fimbriate along upper half. Fruits dull yellow to yellowish brown or orange. Seeds not turgid, 1-loculed ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ T. kirilowii

    • 2. Leaves 3- or 5-(rarely 7-)lobed, lobes rhombic-ovate or oblong-ovate. Fruits orange. Seeds pale yellow to yellowish brown ・・・・・・・・・・・・・・・・・・・ var. kirilowii 하늘타리

    • 2. Leaves 3- or 5-lobed, lobes triangular or triangular-ovate. Fruits yellow. Seeds dark brown ・・・・・・・・・・・・・・・・・・・・・ ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ var. japonica 노랑하늘타리

Acknowledgements

This work was supported by a grant from the National Institute of Biological Resources (NIBR), funded by the Ministry of Environment (MOE) of the Republic of Korea (NIBR201902105).

Notes

Conflict of Interest

The authors declare that there are no conflicts of interest.

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Article information Continued

Fig. 1.

Illustration of Trichosanthes cucumeroides. A. Habit (♂). B. Pistillate flower. C. Seed. D. Fruit.

Fig. 2.

Photographs of Trichosanthes cucumeroides in their habitat. A. Habit. B. Staminate flower. C. Pistillate flower. D. Staminate flower (side view). E. Leaf (adaxial surface). F. Leaf (abaxial surface). G. Fruit.