Cirsium taiwanense Y.H.Tseng & Chih Y.Chang, 2021

Chang, Chih-Yi, Tzeng, Hsy-Yu & Tseng, Yen-Hsueh, 2021, Cirsium taiwanense (Compositae, Cirsium sect. Onotrophe, subsect. Australicirsium), a new species from Taiwan, PhytoKeys 183, pp. 35-53 : 35

Cirsium taiwanense Y.H.Tseng & Chih Y.Chang sp. nov.

Figures 1C , 2C , 3C , 5 , 6

Diagnosis.

Differs from C. hosokawae in having a yellow corolla (vs. vivid purplish red corolla), a narrower angle between the midrib and lateral veins of the cauline leaves ((44-)52-73° vs. 82-90°), and usually more florets (101-135(-194) vs. 54-111) and phyllaries (90-127 vs. 68-109) per capitulum. Differs from C. arisanense by its nodding mature capitula (vs. erect), erect corolla lobes (vs. revolute), and a densely cobwebby abaxial leaf surface (vs. without cobwebby indumentum).

Type.

Taiwan. Nantou County, Ren’ai Township, Provincial Rd. No. 14A 21 km, 2605 m alt., 24.11438°N, 121.21821°E, 15 July 2020. C. Y. Chang 2976 (holotype: TCF; isotype: TNM, PPI) .

Description.

Perennial herbs, stems 0.5-1.0 m tall, internodes terete. Leaves pinnatipartite or pinnatisect, space between pinnae V-shaped, adaxial surface puberulent or cobwebby, abaxial surface densely cobwebby, margin spinose; rosette leaves narrowly elliptic to oblanceolate, base cuneate to attenuate, apex narrowly acute, 19.5-34.1 × 4.1-7.4 cm, angle between the midrib and the lateral veins (40-)55-76°; pinnae 7-11 pairs, 0.9-2.6 × 1.2-2.1 mm, space between pinnae 0.4-1.2 cm, petiole 1.5-4.0 cm; cauline leaves narrowly elliptic to narrowly triangular, base cordate, apex narrowly acute, 9.0-25.5 × 2.2-6.9 cm, angle between the midrib and the lateral veins (44-)52-73°; pinnae 5-8 pairs, 1.3-2.1 × 0.8-1.9 cm, space between pinnae 0.6-1.5 cm, sessile. Capitula solitary or 2-6 arranged into racemes or panicles, mature capitula nodding. Involucre urceolate, more or less cobwebby, 2.8-3.4 × 1.4-1.9 cm; phyllaries 90-127, in 5-7 series, apex acute, midrib distinct, (0.3-)0.5-1.4 × 1.5-2.1 mm, length ratio of inner and outer phyllaries 2.2-3.6, the reflexed part of the phyllaries 1.5-3.1 mm long. Receptacle flat, densely bristly. Florets 101-135(-194), 2.2-3.1 cm long, with yellow corolla, corolla lobes 5, linear, erect, 3.0-5.1 × 0.4-0.7 mm, corolla tube fistulose with 2 sections, the inflated section of corolla tube 4.1-5.8 mm long; synantherous stamens 5, anthers brown, 5.9-8.3 mm long, base with caudate extensions, filaments 3.0-4.5 mm long with irregular protuberances; stigmas bifid, styles 2.0-2.5 cm long, style arm 2.6-2.7 mm long, ovaries (1.6-)3.2-4.1 mm long. Achenes oblong, base acute, apex truncate, beige, 3.5-4.5 × 1.5-1.8 mm, compressed, 4-angled, ribbed, beak heart-shaped; pappus copious, plumose, bristles in many series, 1.55-1.65 cm long, forming basal ring, easily shed.

Phenology.

Flowering between June and October and fruiting between July and November.

Distribution and habitat.

Endemic species of Taiwan. Cirsium taiwanense grows in open areas between Querus forest and Abies forest at 1400-3400 m a.s.l. in central-northern Taiwan. Cirsium taiwanense usually grows at sunny sites. Common companion species are Artemisia morrisonensis Hayata ( Compositae ), Lilium formosanum Wallace ( Liliaceae ), Salix fulvopubescens Hayata ( Salicaceae ) and Rubus pectinellus Maxim. ( Rosaceae ).

Chinese name.

Tai-wan-ji (臺灣薊).

Chromosome number.

2 n = 32 (Fig. 3B ).

Palynology.

Pollen grains are tricolporate, spheroidal, micro-reticulate and 46.6-51.8 × 43.5-50.7 μm (P/E ratio: 0.9-1.1). The surface is densely covered with spines that are 2.8-3.6 μm long and 3.9-6.0 μm wide at the base. The distance between spines is 8.2-11.8 μm (Fig. 2C ).

Conservation status.

Cirsium taiwanense is common in north-central Taiwan (Fig. 4 ). The populations often grow in high mountain areas and experience limited disturbance by humans. Following the International Union for Conservation of Nature (IUCN) Categories and Criteria ( IUCN 2019), we regard this species as of Least Concern (LC).

Additional specimens examined.

Taiwan. Hsingchu County, Jianshi Township, Mt. Itsashan, 7 Sept. 1993. C. L. Huang 78 (HAST!). Miaoli County, Taian Township, en route from 99 lodge to Mt. Tapachienshan, 11 Aug. 1985. C. I Peng 8492, 8542, 8543, 8544, 8545, 8546 (HAST!); same loc., 2 Nov. 1996. C. M. Wang 2384 (TNM!); Taian, 13 Sept. 1996. C. H. Chen 1870 (TAIE!); 99 Lodge, 2780 m alt., 2 Nov. 1996. C. M. Wang 2384 (HAST!); Mt. Hsishihshan, 27 Oct. 1976. B. P. Yang 81 (TAIF!). Taichung City, Heping District, Mt. Nanhutashan, 21 Sept. 1969. T. Yamazaki 281 (TI!); Yunleng cabin to Mt. Duojiatunshan, 26 June 1994. C. M. Wang 1026 (TNM!); en route from entrance to Yunleng cabin, 27 July 2019. C. Y. Chang 2478 (TCF); Derji, 3 July 1974. C. I Peng 15 (TAI!); en route from entrance to Chika Lodge, 1 June 2003. C. M. Wang 6908 (TNM!); same loc., 19 June 2009. C. M. Wang 13025 (TNM!); same loc., 20 Jun. 2011. C. I Huang 5273 (HAST!); same loc., 16 July 2009. Y. H. Tseng 4697 (TCF); same loc., 9 Feb. 2021. C. Y. Chang 3269 (TCF); en route from Chika lodge to Mt. Syue east peak, 7 Aug. 1986. C. I Peng 9660 (HAST!); same loc., 11 Sept. 2002. C. I Huang 1238 (HAST!; TNM!); same loc., 21 June 2011. C. I Huang 5290 (HAST!); en route from Chika lodge to 369 Lodge, 15 June 1985. C. I Peng 7887 (HAST!); behind 369 Lodge, margin of Abies forest, 9 Sept. 2009. C. T. Chao 922 (TCF!); en route from Wuling lodge to Mt. Tao, 24 Aug. 1988. C. I Peng 12012, 12020, 12100 (HAST!); same loc., 22 July 2018. C. Y. Chang 2133 (TCF!); en route from Wuling lodge to Taoshan waterfall, 24 Aug. 1988. C. I Peng 12097 (HAST!); Huanshan, 6 July 2006. Z. H. Chen 186 (TAIF!). Nantou County, Ren’ai Township, Guandaoxi, 22 Oct. 1932. S. Sasao s. n. (CHIA!); Hsinjenkang, Provincial Rd. No. 14A 21 km, 8 Sept. 1997. S. H. Wu 384 (HAST!); Provincial Rd. No. 14A 22 km, 3 Aug. 2011. T. W. Hsu 17059 (TAIE!); Mt. Hohuanshan near Yuanfeng, 13 July 1985. C. I Peng 8327 (HAST!); Nenggao Cross-ridge Historic Trail, 28 Feb. 2006. M. J. Chung x22805 (TAIF!); same loc., 31 Jan. 2018. C. Y. Chang 1609 (TNM); Provincial Rd. No. 14A 21.5 km, 2 Oct. 2015. C. Y. Chang 772 (TNM); same loc., 27 Oct. 2015. C. Y. Chang 839 (TNM).

Figures

Figure 1. Comparison of the morphological characters of Cirsium Mill. subsect. Cirsium Australicirsium Kitam. A C. arisanense Kitam B C. hosokawae Kitam C C. taiwanense Y. H. Tseng & Chih Y. Chang 1 cauline leaf, adaxial view 1 ' cauline leaf, abaxial view 2 capitulum 3 inner phyllary 3 ' middle phyllary 3 " outer phyllary 4 floret 4 ' floret (pappus removed) 5 synantherous stamens 6 style branches 7 achene 7 ' achene with pappus.

Figure 2. Comparison of the pollen morphology of Cirsium Mill. subsect. Cirsium Australicirsium Kitam A C. arisanense Kitam B C. hosokawae Kitam C C. taiwanense Y. H. Tseng & Chih Y. Chang 1 polar view 2 equatorial view 3 colporate view. Scale bar: 30 μm.

Figure 3. Karyotype of Cirsium Mill. subsect. Cirsium Australicirsium Kitam A C. arisanense Kitam., 2 n = 34 B C. hosokawae Kitam., 2 n = 34 C C. taiwanense Y. H. Tseng & Chih Y. Chang, 2 n = 32 1 cell 2 karyogram. * relatively clear satellites; arrow indicates chromosomes with secondary constriction. Scale bar: 5 μm.

Figure 4. Distribution map of Cirsium hosokawae Kitam. (▲) and C. taiwanense Y. H. Tseng & Chih Y. Chang (○) in Taiwan. The red interrupted lines indicate major geographical climate regions as per Su (1985), and the blue dotted lines indicate sections within each climate region. The right part of the figures shows a side view of Taiwan and the vertical lines indicate altitudinal vegetation zones as per Su (1984).

Figure 5. Line drawings of Cirsium taiwanense Y. H. Tseng & Chih Y. Chang A habit B rosette leaf C cauline leaf D capitulum E floret E ' floret (pappus removed) F phyllaries G style branches H achene.

Figure 6. Cirsium taiwanense Y. H. Tseng & Chih Y. Chang A habitat B habit C basal rosette D variations of rosette leaves E variations of cauline leaves F inflorescences G, H capitulum I floret I ' floret (pappus removed) J achenes.