[Botany • 2019] Cirsium tatakaense (Compositae) • A New Species from Taiwan

 Cirsium tatakaense  Y.H.Tseng & C.Y.Chang

in Chang, Tzeng & Tseng, 2019
 DOI: 10.3897/phytokeys.117.29380

Abstract

A new species of Cirsium, Cirsium tatakaense Y.H.Tseng & C.Y.Chang, from central-southern Taiwan is described and illustrated. This species is similar to C. kawakamii Hayata in leaf shape, achene and chromosome number (2n = 64), but can be readily distinguished from C. kawakamii by the narrower leaf lobes, usually higher number of florets and phyllaries, the purplish-red corolla (vs. white) and larger pollen grains. A key to the species of Cirsium in Taiwan is also presented.

Keywords: New species, Chromosome number, Cirsium tatakaense, Cirsium kawakamii, Compositae, Taiwan

Figure 1. Line drawings of Cirsium tatakaense Y.H.Tseng & C.Y.Chang
A habit B root C leaf D capitula E inner phyllary E’ middle phyllary E” outer phyllary F floret F’ floret (pappus removed) G synantherous H style branches I achene. Voucher: C. Y. Chang 1442 (TCF). 

Figure 2. Cirsium tatakaense Y.H.Tseng & C.Y.Chang
A habitat B habit C seedling D variations of leaves E inflorescences F capitula G floret; (right-side pappus removed) H achene with pappus I achene.

Cirsium tatakaense Y.H.Tseng & C.Y.Chang, sp. nov.

Diagnosis: Differs from C. kawakamii in having narrower leaf lobes (7.3−11.7 mm), usually more florets, (136)161−308 and phyllaries (111−199), a purplish-red corolla and larger pollen grains (34.2−42.6 × 35.2−44.7 μm).

Distribution: Endemic species of Taiwan. Cirsium tatakaense is located in open areas of cloud forests of vegetation zones from the Quercus to Abies forest zone at alt. 2000−3000 m in central-southern Taiwan (Fig. 3). Based on the geographical climatic regions and vegetation zones (Su 1984, 1985), C. tatakaense is distributed mainly in the central-west inland regions. Cirsium tatakaense has been discovered in sunny environments, such as roadsides and forest margins, concentrated on the upper portions of hills along Provincial Highway no. 18. Miscanthus transmorrisonensis Andersson (Poaceae), Rubus taitoensis Hayata (Rosaceae) and Senecio nemorensis L. var. dentatus (Kitam.) H. Koyama (Compositae) are often discovered with C. tatakaense. Sometimes, C. arisanense Kitam. and C. ferum Kitam. are found near to C. tatakaense; however, no hybrid individual between these species has been observed.

Chinese name: Ta-ta-jia-ji (塔塔加薊).

Etymology: The species epithet tatakaense derives from the type location Tataka in Nantou County.

Figure 5. Comparison of the morphological characters amongst the species of Cirsium sect. Onotrophe in Taiwan.
A Cirsium tatakaense Y.H.Tseng & C.Y.Chang B C. kawakamii Hayata C C. arisanense Kitam.: 1 leaf 2 capitula 3 inner phyllary 3’ middle phyllary 3” outer phyllary 4 floret 4’ floret (pappus removed) 5 synantherous 6 style branches 7 achene 7’ achene with pappus.

 Chih-Yi Chang, Hsy-Yu Tzeng andYen-Hsueh Tseng. 2019. Cirsium tatakaense (Compositae), A New Species from Taiwan.  PhytoKeys. 117: 119-132. DOI: 10.3897/phytokeys.117.29380