Underestimated diversity in one of the world’s best studied mountain ranges: The polyploid complex of Senecio carniolicus (Asteraceae) contains four species in the European Alps

Abstract

Senecio carniolicus (Asteraceae) is an intricate polyploid complex distributed in the European Alps (di-, tetra- and hexaploids) and Carpathians (hexaploids only). Molecular genetic, ecological, and crossing data allowed four evolutionary groups within S. carniolicus to be identified. Here, we establish that these four groups (two vicariant diploid lineages, tetraploids and hexaploids) are also morphologically differentiated. As a consequence, we draw taxonomic conclusions by characterizing four species, including the more narrowly circumscribed S. carniolicus (lectotypified here), the taxonomically elevated S. insubricus comb. nov. (lectotypified here), and the two newly described species S. disjunctus and S. noricus.

Cytotype variation, cryptic diversity and hybridization in Ranunculus sect. Batrachium revealed by flow cytometry and chromosome numbers

“…In an attempt to change this disappointing state of knowledge, we decided to analyse the variation in ploidy level and genome size in an extensive set of Batrachium populations using flow cytometry (FCM), which (i) is an efficient tool for analysing a large number of individuals rapidly, allowing to reveal the structure of populations and to detect rare cytotypes and hybrids, (ii) is frequently used in studies of evolutionarily and taxonomically intricate groups of plants, including polyploid and hybridogenous complexes (e.g. Suda et al 2010, Trávníček et al 2011a, Chumová et al 2015, Flatscher et al 2015, Lepší et al 2015, Bressler et al 2017, Feulner et al 2017 and homoploid plants (Loureiro et al 2010, Prančl et al 2014, (iii) has been successfully used as a basic method for taxonomic determination and delimitation of other complex aquatic taxa, such as Callitriche (Prančl et al 2014) and Nymphaea (Volkova et al 2010, Kabátová et al 2014, and (iv) has never been used to investigate Batrachium, with the exception of a single R. trichophyllus population (Hidalgo et al 2015). We used flow cytometry combined with chromosome counting to improve our understanding and identification of water-crowfoots in central Europe.…”

Do ploidy level, morphology, habitat and genetic relationships in Alpine Vaccinium uliginosum allow for the discrimination of two entities?

“…Whereas some polyploid complexes have been subjects of systematic evolutionary research for several decades (e.g. Achillea, Clausen et al 1948), others, such as the Senecio carniolicus aggregate, were considered ploidy uniform until recently (Suda et al 2007, Flatscher et al 2015.…”

Genetically divergent cytotypes of Vaccinium uliginosum co-occurring in the central Eastern Alps can be distinguished based on the morphology of their flowers

“…Whereas in the autopolyploid complex of Senecio carniolicus s. lat. the cytotypes are delineated as species (Flatscher et al 2015), in Gymnadenia conopsea s. lat. this is only partly possible because of a mismatch of genetic lineages and morphological groups (Trávníček et al 2011b).…”

“…The chosen experimental design, however, revealed only three mixed-ploidy sites and thus prevented inferences about local niche differentiation. In other groups such as the autopolyploid complex of Senecio carniolicus detailed studies reveal strong niche differentiation among the cytotypes (now delineated as species; Flatscher et al 2015) in spite of their co-occurrence within very short distances (a few decimetres; Hülber et al 2009, Sonnleitner et al 2010. Overall, niche differentiation is considered a prevalent mechanism in maintaining the stable coexistence of cytotypes, which is rarely experimentally demonstrated using reciprocal transplantations (Kolář et al 2017).…”