title: Septal pore complex morphology in the Agaricomycotina (Basidiomycota) with emphasis on the Cantharellales and Hymenochaetales.
abstract: The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales. It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type.
authors.affiliation: CBS Fungal Biodiversity Centre, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
authors.forename: Kenneth G A
authors.initials: KG
authors.lastname: van Driel
authors.forename: Bruno M
authors.initials: BM
authors.lastname: Humbel
authors.forename: Arie J
authors.initials: AJ
authors.lastname: Verkleij
authors.forename: Joost
authors.initials: J
authors.lastname: Stalpers
authors.forename: Wally H
authors.initials: WH
authors.lastname: Müller
authors.forename: Teun
authors.initials: T
authors.lastname: Boekhout
mesh_terms: D001487:Basidiomycota / Q000145:classification / Q000648:ultrastructure*; D020285:Cryoelectron Microscopy; D048690:Fruiting Bodies, Fungal / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission