Phytotaxa 361 (2): 168–182 http://www.mapress.com/j/pt/ Copyright © 2018 Magnolia Press Article PHYTOTAXA ISSN 1179-3155 (print edition) ISSN 1179-3163 (online edition) 168 Accepted by Manuel B. Crespo: 2 Jun. 2018; published: 19 Jul. 2018 https://doi.org/10.11646/phytotaxa.361.2.3 Contribution to the pollen morphology of Tragopogon (Asteraceae) in Turkey MUTLU GÜLTEPE 1 , SERDAR MAKBUL 2,* , SEDA OKUR 3 & KAMİL COŞKUNÇELEBİ 4 1 Deparment of Forestry, Dereli Vocational School, Giresun University, Giresun, Turkey; e-mail: mutlugultepe61@gmail.com 2 Department of Biology, Faculty of Sciences and Arts, Recep Tayyip Erdoğan University, 53100, Rize, Turkey; e-mail: smakbul@hotmail.com 3 Medicinal and Aromatic Plants Program, Pazar Vocational School, Recep Tayyip Erdoğan University , Rize, Turkey; e-mail: seda.okur@erdogan.edu.tr 4 Department of Biology, Science Faculty, Karadeniz Technical University, 61080 Trabzon, Turkey; e-mail: kamil@ktu.edu.tr *author for correspondence Abstract The pollen morphology of 25 Tragopogon L. taxa (including four subspecies and four varieties) distributed in Turkey was studied under light and scanning electron microscopy. It was observed that pollen grains of the examined Tragopogon taxa are suboblate and oblate-spheroidal in shape, and 3-zonocolpororate with fifteen lacunae. The lenghts of the polar axes and equatorial axes range from 31.57 to 40.35 μm and 35.32 to 44.65 μm, respectively. Numerical analyses show that the length of equatorial axis and the pore length are the most valuable characters among nineteen palynological traits for separating the examined taxa. The general palynological characteristics of the examined taxa allow some taxonomical evaluations for the genus. However, the results of cluster and principal component analyses did not support the division of the genus at any subgeneric level; neither did the ligule colour, as reported in the literature. Keywords: Cichorieae, Palynology, Scorzonerinae, Taxonomy Introduction Tragopogon Linnaeus (1753: 789) comprising about 150 species is a closely related genus in the tribe Cichorieae of the Asteraceae (Mavrodiev et al. 2004, Soltis et al. 2004). The genus is widespread in Europe and Asia (Bremer 1994) and has Mediterranean origin (Kuthatheladze 1957). The species of Tragopogon are mostly distributed in semi-arid regions (Bell et al. 2012). Taxonomic complexity is increasing in the genus because of the similar morphology of cryptic species (Suárez-Santiago et al. 2011, Mavrodiev et al. 2012). The first thorough analysis of the genus Tragopogon was provided by Candolle in 1838 (Mavrodiev et al. 2005). Candolle (1838) divided Tragopogon into two distinct groups based on the presence of thickened peduncles below the capitula without formally proposing any taxonomic group. Later, the genus was divided into two unspecified groups according to the ligule colour, named as “Flaviflora” and “Rubriflora” by Boissier (1875). Besides these artificial treatments, Borisova (1964), Rechinger (1977) and Tzvelev (1985) treated Tragopogon under 17 sections in Flora of USSR, 13 sections in the Flora Iranica and 5 sections in the European part of the USSR, respectively. However, there is not a general consensus about any infrageneric treatment within the genus as in several regional floras (Matthews 1975, Richardson 1976, Shi et al. 2011). Matthews (1975) did not use any subgeneric grouping in the treatment of Turkish Tragopogon; however Gültepe et al. (2016) suggested sectional grouping for newly described species from Turkey. In the Flora of Turkey, 22 taxa belonging to 18 species were reported for Tragopogon (Matthews 1975), and two species were added in Supplement I for the Turkish Flora (Davis et al. 1988). However, recent research on Tragopogon suggests that the genus is represented with 25 taxa in Turkey (Gültepe et al. 2016). Palynological studies have shown that pollen features have great taxonomic value within closely related taxa in the Asteraceae (Blackmore 1982, 1990, Punt & Hoen 2009). Wodehouse (1935) examined the pollen morphology of the Lactuceae including several members of the Scorzonerinae [Scorzonera Linnaeus (1753: 790), Geropogon Linnaeus