Abstract Detail

Pteridology

Howard, Cody [1], Kamau, Peris [2], Vare, Henry [3], Hannula, Liina [3], Juslen, Aino [3], Rikkinen, Jouko [4], Sessa, Emily [5].

Historical biogeography of African Asplenium (Aspleniaceae).

Asplenium is one of the most taxon-rich lineages of ferns, with >700 species described worldwide, and a predominantly pantropical distribution. It is by far the most diverse genus of ferns in Africa, with 175 recognized taxonomic entities (the next-most-diverse genus of ferns in Africa, Elaphoglossum, has 76 recognized African taxa). Previous phylogenetic studies show that Asplenium has multiple independent African lineages, and several of these appear to have diversified on the continent. Age estimates for Asplenium suggest that long-distance dispersal is likely responsible for the ancestors of Asplenium reaching sub-Saharan Africa. However, the temporal origins of Asplenium have been historically difficult to estimate confidently. Therefore, it remains to be thoroughly explored where and when Asplenium arose and whether vicariance has played any role in the overall biogeographical history of African Asplenium. Additionally, determining the direction of dispersals for African taxa (i.e., into or out of Africa) as well as the biogeography of Asplenium within Africa have yet to be studied. Here, we employ multiple methods to investigate the evolution and biogeography of sub-Saharan African Asplenium. From our dataset, we find that all dispersals into Africa likely occurred within the last ~35 My, with the majority coming from Asia. We also find that two independent subclades appear to have diversified within sub-Saharan Africa after their ancestors' arrival.

1 - University of Florida, Department of Biology, Gainesville, FL, USA
2 - National Museums of Kenya, Nairobi, Kenya
3 - Finnish Museum of Natural History, Helsinki, Finland
4 - University of Helsinki, Department of Biosciences, Helsinki, Finland
5 - University Of Florida, Biology, Box 118525, 521A Bartram Hall, Gainesville, FL, 32611, United States

Keywords:
Asplenium
ferns
Africa
biogeography
divergence time estimation
pteridophytes.

Presentation Type: Oral Paper
Session: PTR1, Pteridology I
Location: /
Date: Monday, July 19th, 2021
Time: 10:30 AM(EDT)
Number: PTR1003
Abstract ID:166
Candidate for Awards:Edgar T. Wherry award