Abstract Detail

Pteridological Section/AFS

Sundue, Michael [1], Parris, Barbara [2], Ranker, Tom [3], Smith, Alan [4], Fujimoto, Erin [3], Zamora-Crosby, Delia [5], Morden, Clifford [3], Chiou, Wen-Liang [6], Chen, Cheng-Wei [7], Rouhan, Germinal [8], Hirai, Regina [9], Prado, Jefferson [9].

Global biogeography and diversification of grammitid ferns.

The goal of our study was to examine the global historical biogeography and lineage diversification rates of grammitid ferns (Polypodiaceae) within a phylogenetic context. We inferred phylogenetic relationships of 190 species representing 31 of the 33 currently recognized genera of grammitid ferns by analyzing DNA sequence variation of five plastid DNA regions. We estimated the ages of cladogenetic events on an inferred phylogeny using secondary fossil calibration points. Historical biogeographical patterns were inferred via ancestral area reconstruction techniques. Comparative lineage diversification rates were estimated across the dated phylogeny using several methods. Our results supported several large-scale phylogenetic and biogeographic patterns: 1) a monophyletic grammitid clade that arose among Neotropical polypod ancestors about 31.4 Ma; 2) a paraphyletic assemblage of clades distributed in the Neotropics and the Afro-Malagasy region; 3) a large clade distributed throughout the Asia-Malesia-Pacific region that originated about 23.4 Ma; and, 4) an Australian origin of the circumaustral genus Notogrammitis. Most genera were supported as monophyletic except for Grammitis, Oreogrammitis, Radiogrammitis, and Zygophlebia. Although estimates of lineage diversification depended on the method employed, there was support for differential rates of speciation among clades. Grammitid ferns are a well-supported monophyletic group with two biogeographically distinct lineages: a primarily Neotropical grade exhibiting several independent successful colonizations to the Afro-Malagasy region and a primarily Paleotropical clade exhibiting multiple independent dispersals to remote Pacific islands and temperate, austral regions. Most recognized genera were supported as monophyletic. The early diversification of grammitids produced one lineage that exhibits relatively slow diversification rates and a more rapidly diversifying and, hence, more species-rich, sister lineage. Diversification rates also increased in the circumaustral genus Notogrammitis, relative to its sister lineage. We also found evidence that diversification rates increased in a Neotropical Andean lineage comprising several genera and the large Paleotropical clade, both of which are characterized by species commonly occurring in high elevation cloud forests and/or other specialized habitats.

1 - 111 Jeffords Hall, 63 Carrigan Dr., Burlington, VT, 05405, USA
2 - Fern Research Foundation, 21 James Kemp Place, Kerikeri, Bay of Islands, New Zealand
3 - University of Hawaii at Manoa, Department of Botany, 3190 Maile Way, Room 101, Honolulu, HI, 96822, USA
4 - University of California, University Herbarium, Berkeley, CA, 94720, USA
5 - The University of Vermont, Department of Plant Biology, The Pringle Herbarium, 27 Colchester Ave, Burlington, VT, 05405, USA
6 - TAIWAN FORESTRY RESEARCH INST, 53 NAN-HAI RD, TAIPEI, 100, Taiwan
7 - Taiwan Forestry Research Institute, 53 Nan-Hai Rd, Taipei, 100, Taiwan
8 - Museum national d’Histoire naturelle, Herbier national, 16 rue Buffon CP39, Paris, F-75005, France
9 - Instituto de Botânica, Caixa Postal 68041, CEP 04045-972, São Paulo-SP, Brazil

Keywords:
Polypodiaceae
grammitids
Biogeography
diversification.

Presentation Type: Oral Paper:Papers for Sections
Session: 12
Location: Pines North/Boise Centre
Date: Monday, July 28th, 2014
Time: 4:45 PM
Number: 12013
Abstract ID:299
Candidate for Awards:None