Abstract Detail

Systematics Section/ASPT

Bigott, Adam [1], Willyard, Ann [1].

Oral: Are the Sky Island Pines Unique?

At present, most taxonomists accept about 17 species of subsection Ponderosae (Pinaceae), but many suspect that there are additional cryptic taxa hidden within the broadly described Pinus ponderosa. The sky islands are a collection of isolated mountains in the desert of the American southwest and potentially home to one of these cryptic species. Putatively distinctive morphological features such as predominantly three needles per fascicle lead some to propose that the sky island ponderosa are distinct from the ponderosa pine of the Rocky Mountains, as well as being distinct from sympatric P. arizonica. This proposal affects whether the name P. brachyptera Engelm., collected in 1846 near Santa Fe, NM, is applied to the sky island ponderosa as well as to the ponderosa pines of the southern Rocky Mountains. Chloroplast and nuclear simple sequence repeats and mitochondrial haplotypes were genotyped for 12 populations from the Sky Islands, nearby contiguous forests, and sympatric P. arizonica and P. engelmannii to investigate the potential for introgressive hybridization. Using clustering algorithms, we created a visual representation of the genetic variation. We also used Ecological Niche Modeling based on 19 biologically meaningful climate variables to test if the current geographic distribution of the sky island pines represents an ecological niche that is distinct from the Rocky Mountain habitat. We discuss the usefulness of considering four independent criteria (three molecular and one ecological) to support species delimitation questions: i) are the sky island pines a unique species; or ii) are the sky island pines, as well as the ponderosa pines of the southern Rocky Mountains, a single taxon?

Broader Impacts:

1 - Hendrix College, Biology Dept, 1600 Washington Ave, Conway, AR, 72032, USA

Keywords:
species complex
microsatellites
niche modeling.

Presentation Type: Oral Paper:Papers for Sections
Session: 18
Location: Magnolia/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 9:15 AM
Number: 18004
Abstract ID:478
Candidate for Awards:None