Numbers to names – restyling the Fusarium incarnatum-equiseti species complex

The Fusarium incarnatum-equiseti species complex (FIESC) is a phylogenetically species-rich complex that includes over 30 cryptic phylogenetic species, making identification based on phenotypic characters problematic. Several established Fusarium species known to reside in the FIESC lack type material, further complicating the use of Latin binomials for this complex. To overcome this problem, an informal classification system based on a haplotype nomenclature was introduced to improve communication between researchers in various fields. However, some conflicts in the application of this nomenclature system have arisen. To date, 16 phylo-species in the FIESC have been provided with Latin binomials with approximately 18 FIESC phylo-species still lacking Latin binomials, the majority of which reside in the Incarnatum clade. The aim of this study is to introduce Latin binomials for the unnamed FIESC phylo-species based on phylogenetic inference supported by phenotypic characters. The three-gene (calmodulin, RNA polymerase II second largest subunit and translations elongation factor 1-alpha) phylogenetic inference resolved 47 lineages, of which 44 belonged to the FIESC. The F. camptoceras species complex (FCAMSC) is introduced here for three lineages that are distinct from the FIESC. Epitypes are designated for F. compactum, F. incarnatum and F. scirpi, and a neotype for F. camptoceras. Latin binomials are provided for 20 of these newly resolved phylo-species in the FIESC.