Disentangling the kinship of Serapias × todaroi Tin. (Orchidaceae) along the eastern Adriatic using chromosome count and morphometry

•The hybridogenous nature of S. × todaroi along the Croatian coast was studied.•Chromosome count and morphology analysis were performed.•The results support the parenthood of S. lingua and S. parviflora.•The hybrid is of intermediate features, but floristically more similar to S. lingua.•Base of the labellum, plant height and flower size are most relevant for identification.