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Tabaripour R, Sheidai M, Talebi SM, Noormohammadi Z. 2018. Genetic divergence and speciation within Ziziphora capitata (Lamiaceae): Molecular and micromorphological evidences. Biodiversitas 19: 697-705. Ziziphora capitata is a member of the Mint family (Lamiaceae) that naturally grows in various regions. Different subspecies have been reported for this species, from which two are recorded from Iran: Z. capitata subsp. capitata, and Z. capitata subsp. orientalis. In the present study, morphological, palynological and molecular (ISSR and cp-DNA) data were used to reveal speciation within this species and reconsider taxonomic rank of its presumed subspecies. The obtained results revealed a great difference between two presumed subsp. of Z. capitata. These taxa differed in morphological, palynological and molecular characteristics. Statistical and bioinformatics tests revealed significant genomic difference between them and phylogenetic analyses showed that they have a close affinity to some other Ziziphora species (out-groups used), then to each other. Bayesian and maximum parsimony phylogenetic trees differentiated the presumed sub-species of Z. capitata. Moreover, K-Means clustering and Bayesian analysis of genetic groups by Evanno test (optimal k) supported the presence of two distinct genetic groups within Z. capitata. This approach objectively defines a threshold separating intraspecific population substructure from interspecific divergence, which is the general aim of species delimitation studies. Therefore, the present study provides enough evidence for introducing two separate species within Z. capitata based on the traditional taxonomy as well as combination of molecular and micro-morphological data.

The subtribe Loliinae is one of the largest subtribes of Poeae with about 600 species.Festuca is a large genus with close relations to other genera as Lolium, Castellia, and Vulpia. The taxonomic history of the Festuca-Lolium species group is very complicated. The polyploidy and hybridization make it more confusing. Due to the morphological similarities between genera identification is very difficult, the aim of the present study is to provide the taxonomic characters for the delimitation of the taxa of subtribe Loliinae. We used scanning electron microscopy (SEM) techniques for the evaluation of the lemma and palea surface micromorphology for 33 species of this subtribe. Multivariate statistical analysis was used to show the species groupings.Factor analysis based on the principal component analysis showed the diagnostic importance of each of the characters. The lemma and palea epidermal patterns of Castellia, Festuca, and Lolium were examined, and results revealed that Lolium and Vulpia sensu lato species made separate groups nested in the Festuca clusters. The length of the long cell of the lemma, prickle in the lemma and palea, the wall shape of long cells of the lemma, wax type, silica bodies of lemma and palea, and the short cells in palea were important diagnostic characters for the species studied. The measured and evaluated set of lemma and palea micromorphological features was unable to provide the delimitation of the Festuca genus as subgeneric or sectional level.Present observations illustrated a heterogeneous assemblage as Festuca that needs further study for delimitation.

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