Mickelia

Abstract: The perispores of 48 species of bolbitidoid ferns (Mickelia, Arthrobotrya, Bolbitis, Elaphoglossum, Lomagramma, and Teratophyllum) were studied with an SEM. The species studied were those used in a published phylogenetic analysis. For each species, five perispore characters were scored and optimized onto a published molecular tree. A loose, nonappressed perispore with broad folds optimizes as ancestral for the bolbitidoids. The only exception is Lomagramma, for which the perispore adheres tightly to the exospore—a character state that optimizes as a synapomorphy for that genus. In the bolbitidoids, thin crests evolved from broad folds seven times. The presence of thin crests in Mickelia optimizes as a synapomorphy for that genus. The presence of fine surface detail, here termed “microstructure,” was present in nearly all bolbitidoids and optimized as ancestral. Microstructure consisted of spicules, minute crests, and verrucae. The presence of verrucae optimizes as a synapomorphy for Lomagramma. The perisp...

Abstract: Although a worldwide phylogeny of the bolbitidoid fern genus Elaphoglossum is now available, little is known about the phylogenetic position of the 34 Cuban species. We performed a phylogenetic analysis of a chloroplast DNA dataset for atps-rbcL (including a fragment of the gene atps), rps4-trnS, and trnL-trnF. The dataset included 79 new sequences of Elaphoglossum (67 from Cuba) and 299 GenBank sequences of Elaphoglossum and its most closely related outgroups, the bolbitidoid genera Arthrobotrya, Bolbitis, Lomagramma, Mickelia, and Teratophyllum. We obtained a well-resolved phylogeny including the seven main lineages recovered in previous phylogenetic studies of Elaphoglossum. The Cuban endemic E. wrightii was found to be an early diverging lineage of Elaphoglossum, not a member of E. sect. Squamipedia where it was previously classified. We propose a new section for this species: E. sect. Wrightiana. The early diverging position of E. wrightii is of particular interest because the species is a root climber (i.e., climbing from the soil on the lower portions of tree trunks and not losing its connection with the soil), a growth habit it shares with its closest bolbitidoid outgroup genera. This suggests that holoepiphytism evolved later in Elaphoglossum, and the primary hemiepiphytism of E. amygdalifolium, which is sister to the rest of the genus, was derived independently from ancestors that were root climbers. Based on our phylogenetic analysis and morphological investigations, the species of Cuban Elaphoglossum were found to occur in E. sects. Elaphoglossum, Lepidoglossa, Polytrichia, Setosa, and Squamipedia.