Phylogenetic and Morphological Analyses Support the Resurrection of Dendroconche and the Recognition of Two New Genera in Polypodiaceae Subfamily Microsoroideae

Abstract

Abstract—The taxonomy of the Polypodiaceae subfamily Microsoroideae is highly problematic, especially with respect to the circumscription of the highly variable and non-monophyletic genus Microsorum. Using phylogenetic analyses and morphological evidence, we demonstrate that sixteen taxa typically treated in the genera Microsorum and Colysis are not closely related to those groups and instead belong to three clades that are successive sister groups to the Old-World ant-fern genus, Lecanopteris. We use the available genus name Dendroconche for one of these clades and propose the new genera Bosmania and Zealandia to accommodate the remaining two groups. We provide a description and identify morphological synapomorphies for each of the genera, make new combinations and designate lectotypes where necessary, and present keys and descriptions for all relevant species. We also discuss the evolution of ant-fern associations in the lecanopteroid ferns and highlight the need for additional taxonomic work in the subfamily. The following new combinations are provided: Bosmania lastii, B. leandriana, B. membranacea, Dendroconche ampla, D. latilobata, D. linguiforme, D. sayeri, D. scandens, D. varians, Zealandia novae-zealandiae, Z. powellii, Z. pustulata, Z. pustulata subsp. howensis, and Z. vieillardii.