Fruit anatomy of the genus Prangos (Apiaceae) in Iran and its systematic implication

The genus Prangos Lindl. belongs to the Apiaceae (Umbelliferae), subfamily Apioideae and tribe Apieae. This genus with about 45 species is one of the biggest genera of the family. Prangos includes 15 species in Iran, of which seven are endemics. In this study, the fruit anatomy of all species of the genus Prangos in Iran has been investigated comparatively based on the transverse sections of the mericarp. As a result, we could identify and group the species of this genus based on the anatomical features (similarities and differences among species) of the fruit. The species have been divided into four groups based on anatomical characteristics such as the mericarp structure, vallecular vittae, vascular bundle, and rib secretory ducts. Group I corresponds with two subgenera Koelzella (P. pabularia), and Prangos (sections Latilobae and Ulopterae), group II with subgenus Prangos sections Meliocarpoides and Prangos, group III subgenus Prangos with the remainder species of the section Prangos, and group IV with subgenus Prangos section Alococarpum. Anatomical studies also confirmed the morphological and anatomical differences among sections Alococarpum, Latilobae, Ulopterae, and other members of the genus. Furthermore, the anatomical features confirm the transformation of P. eriantha from Alococarpum to Prangos. In addition, based on fruit morphological and anatomical characteristics, a key for the identification of Prangos species has been provided.