The Turkish EndemicPseudodelphinium turcicum(Ranunculaceae): An Unusual Population ofDelphiniumwith Peloric Flowers That Has Persisted in the Wild for 20 Years
Résumé
Premise of research. The Turkish endemic Pseudodelphinium turcicum (Ranunculaceae) was described by Vural et al. (2012) based on a single population found in the salt lake basin of Tuz Gölü, Konya Province. Although the authors noticed morphological similarities between the plants and Delphinium or Garidella, they highlighted unusual features, which led them to describe a new genus consisting of a single species, P. turcicum. The aim of this study is to investigate the morphological particularities and evolution of Pseudodelphinium. Methodology. We carried out morphological, anatomical, and palynological studies on individuals of P. turcicum. We also conducted a molecular phylogenetic analysis to identify the closest relatives of this species. Pivotal results. This combination of approaches shows that the species belongs in the group of Mediterranean species in Delphinium subg. Delphinium. Based on our sampling, P. turcicum is more precisely sister to the Turkish endemic Delphinium venulosum. The perianth of P. turcicum flowers consists of tepals that are, anatomically speaking, similar to the sepals of Delphinium. A second type of perianth organs was evidenced. They are located between the tepals and the stamens, and their development is arrested at an early stage, therefore being comparable to the ventral petals of Delphinium flowers. The pollen of P. turcicum is heteromorphic. Conclusions. We conclude that the population of P. turcicum is an unusual population of Delphinium presenting peloric flowers (through ventralization) that has been maintained in the wild for at least two decades. We provide hypotheses concerning the identity of the floral organs, as well as an explanation for the origin of the particular floral morphology.
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