Abstract Detail

Pteridological Section/AFS

Vasco, Alejandra [1], Loriga, Josmaily [2], Moran, Robbin [1].

Systematics and Phylogeny of Elaphoglossum section Squamipedia.

Elaphoglossum contains about 600 species and is one of the world’s largest fern genera. It is pantropical with about 85% of its species in the New World. We estimate about 75% of the species are epiphytes. The genus is highly uniform morphologically; nearly all the species have simple leaves with free veins. The relationships within the main clades are becoming better understood thanks to molecular phylogenetic analyses and monographic revisions. The aim of the present study was to provide a phylogenetic hypothesis of the relationships for the 20 taxa belonging to E. sect. Squamipedia, based on non-coding chloroplast DNA sequence data. This group of Elaphoglossum is intriguing because within it there are four species, all neotropical, that are highly unusual in the genus because they have dissected leaves. Dissected leaves occur elsewhere in the genus only in two species. We wanted to use the phylogeny as a framework to answer the following questions: 1) Is E. sect. Squamipedia monophyletic? 2) Are the species previously recognized by us and other taxonomists as part of the section monophyletic? 3) What are the phylogenetic relationships among the species and forms? 4) Do the divided-leaved species form a clade, or have they evolved independently?. We found that E. sect. Squamipedia was resolved as monophyletic except for Elaphoglossum wright, a Cuban endemic, which was previously classified in E. sect. Squamipedia. The species recognized in our recent taxonomic revision of E. sect. Squamipedia were supported by our phylogenetic analysis of molecular evidence except for Elaphoglossum lloense and Elaphoglossum squamipes, which were resolved in multiple clades. In the monographic work we chose not to recognize the clades as distinct species because there is no way to distinguish them morphologically. Our phylogenetic results resolved E. sect. Squamipedia as having two main clades, one composed of Madagascan species and the other of neotropical species; the spores of the Madagascan species are non-echinulate, whereas those of the neotropical ones are echinulate. The four species with dissected leaves were resolved in different places on the tree, suggesting all had independent origins from ancestors with simple leaves.

Broader Impacts:

1 - The New York Botanical Garden, Institute of Systematic Botany, 2900 Southern Blvd., Bronx, NY, 10458, USA
2 - University of Munich (LMU), Systematic Botany and Mycology, Munich, 80638, Germany

Keywords:
ferns
Dryopteridaceae
cpDNA.

Presentation Type: Oral Paper:Papers for Sections
Session: 34
Location: Melrose/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 4:00 PM
Number: 34010
Abstract ID:198
Candidate for Awards:Edgar T. Wherry award