Serratula coronata ( Asteraceae ) – a new species record for the flora of Azerbaijan

Serratula coronata (Asteraceae) is reported for the first time for the flora of Azerbaijan. The species was first found during the field surveys in 2012 in the forest edge near the village of Qonaqkend in Quba District of Azerbaijan, and later (in 2014) also discovered between Arafsa and Leketaq villages in the Nakhchivan Autonomous Republic. Data on distribution of species of Serratula sensu lato in the Caucasus are briefly reported and summarized. Diagnostic characters distinguishing S. coronata from other related taxa are provided. Plant communities with participation of S. coronata in Azerbaijan are characterized. Recent data on taxonomy of Serratula and related taxa are briefly discussed.

The family Asteraceae (Compositae, nom.altern.)was reported to be represented in the flora of Azerbaijan by ca.580 species belonging to 125 genera (Agadjanov, 1961); however, the exact numbers of species and genera are subject to changes due to recent changes in taxonomy and nomenclature.Several genera and species of the family, such as Centaurea L., Pyrethrum Zinn.sensu stricto (now Tanacetum L. sensu lato), etc., were studied in Azerbaijan in detail (Askerova, 1970;Qusenovа et al., 2013Qusenovа et al., , 2014;;Mustafayeva, 2013;Mustafayeva et al., 2017); however, some groups of the family are still insufficiently known in the country.In the 20 th century, seven species of Serratula L. sensu lato were reported for the territory of Azerbaijan (Agadjanov, 1961) Wagenitz, 1959Wagenitz, , 1975;;Wagenitz, Hellwig, 1996).Serratula coronata and S. erucifolia have not been yet reported from Azerbaijan.
Reliable diagnostic characters for identification of species of Serratula and Klasea include pollen types, chromosome numbers, along with arrangement of florets, seriate pappus, phyllaries, apendages, etc., but in general identification of species belonging to that group of Asteraceae is complicated.Eight pollen types were distinguished among taxa of the subtribe Centaureinae and, according to the pollen evolution, the genera Serratula, Crupina (Pers.)DC., Rhaponticoides Vaill., Psephellus Cass., Centaurea, and the Acrocentron and Jacea groups of Centaurea sensu lato were evolutionarily ranked based on their main pollen types by Wagenitz (1955).Later, Serratula, Crupina and Rhaponticoides were accepted as "primitive" (with mainly ancestral pollen characters), Psephellus (including P. dealbatus (Willd.)K.Koch = Centaurea dealbata Willd., and related taxa), the Centaurea Cyanus and Centaurea Montana groups -as intermediate, but the Acrocentron and Jacea groups of Centaurea -as advanced types.
The Serratula type with spiny pollen grains was placed in the evolutionarily basal (early-branching) part of the cladogram of Centaureinae (Garcia-Jacas et al., 2001).
Progress in taxonomy, beginning from the last decades of the 20 th century, especially due to molecular phylogenetic studies, brought more clarity to the taxonomic positions of genera, also necessitating numerous taxonomic changes and nomenclatural rearrangements within subtribes, tribes, and genera.Recent molecular phylogenetic studies indicated that the genus Serratula, as traditionally understood, is not a monophyletic group (Martins, Hellwig, 2005;Martins, 2006;Dogan et al., 2015).In particular, the segregate genus Klasea is currently recognized as distinct from Serratula sensu stricto (Ranjbar et al., 2015).However, the species S. coronata remains in the genus Serratula sensu stricto.
Herbarium specimens were collected in subalpine meadows of Qonaqkend village in Quba District, at elevation 1900 m above sea level [a.s.l.] (GPS coordinates N41°12´03.8´´,E048°13´21.7´´, collection date 11 August 2012) and between Arafsa and Leketaq villages in Nakhchivan Autonomous Republic of Azerbaijan at elevations 1700-1800 m a.s.l.(GPS coordinates N41°05´546´´, E048°27´37.0´´, collection date 23 July 2014).In both cases the plants were found growing under meso-xerophytic conditions.Specimens were identified based on morphology and taking into account the main diagnostic characters.

Conclusions
Asteraceae/Compositae has been studied in Azerbaijan mainly during the 1950s-1960s and, based on collected information and herbarium data, the eighth volume of the Flora of Azerbaijan has been compiled (Flora Azerbaidzhana, 1961).This represents the main source for identification and analyzing the species of the family in the flora of Azerbaijan.As mentioned above, seven species of Serratula sensu lato recorded in the Flora of Azerbaijan (1961) and eight species in the Conspectus florae Caucasi (2012).Most of them were recently transferred to the segregate genus Klasea.Currently only two species known from Azerbaijan, S. erucifolia and S. coronata, are still considered as belonging to the genus Serratula sensu stricto.
As well known, over the last 40 years large-scale changes were introduced in Asteraceae systematics; in particular, tribal limits have been significantly reshaped (Funk et al., 2009).Considering taxonomic and nomenclatural changed proposed and accepted for Asteraceae, there is the urgent need to analyze the family in Azerbaijan at the level of tribes and genera.The number and list of species recorded in the flora of the country should be also further updated and specified in the future.