Protoderm versus fundamental meristem origin of the fiber strands in cyperaceae: terminology implications

(Protoderm versus fundamental meristem origin of the fiber strands in Cyperaceae: terminology implications). Among the characters considered common in Cyperaceae and frequently used in the taxonomy and phylogeny of the family, fiber strands stand out. For these, different terminologies are used, among them the term hypodermis, which is a tissue originating in the fundamental meristem. In this context, investigation of tissue origin enables a more precise use of appropriate terminology and homology determination. Thus, this study aims to investigate the ontogeny of these sclerenchyma strands located near the epidermis, in order to confirm their origin and propose standardization of the terminology. An anatomical survey was conducted on sections of the rhizome, including the vegetative apex and leaves, of 11 Cyperaceae species. It was observed that the subepidermal fiber strands originate from the protoderm in all species studied. Only on the adaxial side of the leaf blade of Fimbristylis dichotoma (L.) Vahl the subepidermal fiber strands originate from the fundamental meristem. It is suggested to use of the term subepidermal fiber strands for the grouping of fibers with origin in the protoderm, located near the epidermis and without connection to the vascular tissues.