Dianthus koreanus D.C. Son & K. Lee, 2017

Son, Dong Chan, Kim, Hyun-Jun, Chang, Kae Sun, Lee, Dong-Hyuk & Lee, Kang-Hyup, 2017, A new species of Dianthus (Caryophyllaceae) from Republic of Korea, Phytotaxa 303 (1), pp. 71-76 : 71-74

Dianthus koreanus D.C. Son & K. Lee , sp. nov. ( Figs. 1 , 2 )

Type:— KOREA. Prov. Gyeongsangbuk-do, Uljin-gun, Giseong-myeon, Mangyang-ri , Giseongmangyang beach, elevation 30 m, 36.83455°N, 129.44336°E, 16 July 2015, Lee 2453 (holotype KH-1460258!, isotype KH-1460259!) .

Diagnosis: Herbs perennial, 25–50 cm tall. Roots woody. Stems laxly caespitose, ascending at base, often somewhat woody towards base, densely pubescent. Leaves sessile, coriaceous; cauline leaves opposite, oblanceolate to oblong (2.5–4.5 × 0.5–1.5 cm), mid-vein prominent, apex acute to obtuse, base cuneate to attenuate, base amplexicaule, margins short ciliate, both surfaces densely pubescent, greenish-gray coloured; sterile shoot leaves similar to cauline ones, developing at flowering season. Flowers solitary or in dense cymes; pedicel 0.5–1.4 cm long; bracts 3 pairs, elliptic to obovate, about 1/4–1/2 as long as calyx, margin membranous-ciliate, apex acute. Calyx gamosepalous, cylindrical, 1.5–2.5 cm long, 5-toothed, with many parallel veins. Petals limb bright red, purple-red or pink-coloured, obovate-triangular (1.3–1.5 cm long), apex irregularly toothed; throat spotted and laxly bearded. Stamens 10, exserted, versatile; filaments long, slender; anthers blue-colored. Ovary 1-locular, on a short gynophore, with chartaceous cap; ovules many on free central placenta; styles 2, linear, longer than ovary, pubescent. Capsule cylindrical, 2.0– 2.5 cm long, surrounded by calyx, apex 4-toothed. Seeds black, flat, orbicular.

Etymology: The specific epithet of the new species is dedicated to the country Korea.

Phenology: Flowering time late July–early August; fruiting time late August–September.

Vernacular (Korean) name: Gaet-ba-wi-pae-raeng-i-kkot (±바ŖṂṞOiṈ; new Korean name).

Distribution: Endemic to the Province Gyeongsangbuk-do ( Republic of Korea).

Habitat and ecology: Dianthus koreanus grows on the rocks on the sunny seashores in the eastern coast of Korea ( Figs. 2 , 3 ). Its habitat is dominated by Pinus thunbergii Parlatore (1868: 388) , with Arabis erecta Kim & Jang (2016: 280), Cnidium japonicum Miquel (1867: 60) , Lathyrus japonicus Willdenow (1802: 1092) and Aster spathulifolius Maximowicz (1871: 216).

Conservation status: on the basis of the IUCN Red List categories and criteria ( IUCN 2014), Dianthus koreanus covers a EOO of approximately 30 km 2. The new species is here assessed as Critically Endangered (CR, criterion B1a).

Taxonomic notes: Dianthus koreanus shows morphological similarities with D. chinensis Linnaeus (1753: 411) concerning its spotted, toothed petals, and arrangement of cyme flowers (see Charkevicz 1996, Dequan & Turland 2001, Hong 2007). Despite these similarities, there are clearly differences between these two species such as shape and texture of leaves, and number and shape of bracts ( Table 1 ), as well as the habitat (rocky seashore for D. koreanus vs. mountains for D. chinensis ). D. kiusianus Makino (1912: 178) , which is found in Japan as endemic, and D. japonicus Thunberg (1784: 417) , which is found in Japan, Korea, and China, also display coriaceous leaves, 3 pairs of bracts, and grows on the seashores ( Dequan & Turland 2001, Akiyama 2006, Hong 2007). However, the new species differs from them by its pubescent stem and leaves and throat spotted, and from the latter by its inflorescence shape, apex acute, and elliptic to obovate-shaped bracts, and flat, orbicular seeds ( Table 1 ).

An identification key between concerning the Korean Dianthus species follows:

1. Inflorescences head-like with numerous clustered flower; pedicel short or subsessile (less than 0.2 cm long) .............................. 2

- Inflorescences loose few-flowered cymes or flower solitary; pedicels usually elongate (more than 0.5 cm long) ......................... 3

2. Leaves lanceolate; bracts ovate, equaling or slightly longer than calyx ......................................................................... D. barbatus

- Leaves ovate to ovate-elliptic; bracts elliptic, 1/3–1/2 as long as calyx ....................................................................... D. japonicus

3. Petals lobed to irregularly toothed on upper margin ........................................................................................................................ 4

- Petals fimbriate ................................................................................................................................................................................. 7

4. Flower 3–4 cm in diameter, strongly fragrant; calyx margins ciliate; capsules ovoid ............................................. D. caryophyllus

- Flower 1–2.5 cm in diameter; mildly or inconspicuously fragrant; calyx margins glabrous; capsules cylindrical ......................... 5

5. Leaves linear-lanceolate, chartaceous; bracts in 1 or 2 pairs, ovate ................................................................................................. 6

- Leaves oblanceolate-oblong, coriaceous; bracts in 3 pairs, elliptic to obovate............................................................... D. koreanus

6. Bracts in 1 pairs, apex subulate; calyx 1.2–1.4 cm long .................................................................................................... D. repens

- Bracts in 2 pairs, apex long acuminate; calyx 1.5–2.5 cm long ..................................................................................... D. chinensis

7. Bracts in 2 or 3 pairs, obovate, about 1/4 as long as calyx, apex subulate or long acuminate; calyx usually reddish-purple, 2.5–3.0 cm long; capsules as long as or slightly longer than calyx ............................................................................................. D. superbus

- Bracts in 3 or 4 pairs, ovate, about 1/5 as long as calyx, apex mucronate; calyx green, 3.0–4.0 cm long; capsules shorter than calyx ............................................................................................................................................................................. D. longicalyx

Additional specimens examined (paratypes):— KOREA. Prov. Gyeongsangbuk-do, Uljin-gun, Giseong-myeon, Mangyang-ri , Giseongmangyang beach, 08 September 2016, Son s.n. ( KH!); Prov. Gyeongsangbuk-do, Yeongdeokgun , Chuksan-myeon , Chuksan-ri , Chuksan port, 2 November 2016, Lee 0200 ( KH!) .

Figures

FIGURE 1. Illustration of D. koreanus D.C. Son & K. Lee. WP. Plant. A. Flower. B. Pistil. C. Stamen. D. Calyx. E. Bracts. F. Capsule. G. Seed. H. Stem. I. Leaves. Illustrations by Hyeryun Jo.

FIGURE 2. Photograph of D. koreanus D.C. Son & K. Lee. A. Habitat. B. Stem. C. Sterile shoot leaves. D. Leaves. E. Flower. F. Bracts. G. Bracts (outer bract, mid bract, inner bract from left to right). H. Capsule. I. Seeds. Photographs by Kang-Hyup Lee and Dong Chan Son.

FIGURE 3. Distribution map of D. koreanus D.C. Son & K. Lee (right: zoomed in area in Google Maps of boxed area on left). Illustrations by Dong Chan Son.