Abstract Detail

Systematics Section/ASPT

Edwards, Molly [1], Stévart, Tariq [2], Geerinck, Daniel [3], Simo, Murielle [4], Droissart, Vincent [5], Micheneau, Claire [6], Plunkett, Gregory [7].

Taxonomic revision and molecular phylogeny of Ancistrorhynchus (Orchidaceae), an Angraecoid genus from continental Africa.

Angraecoid orchids are one of the most taxonomically problematic groups in the family. To help overcome this gap, four key angraecoid groups were examined, each centered in Central Africa, and representing a total ca. 40 taxa. These include two sections of Angraecum and two morphologically well delimited genera (Ancistrorhynchus and Bolusiella). In this context, a taxonomic revision of the genus Ancistrorhynchus has been initiated using morphological characters. Detailed examination of 300 dried and alcohol-preserved specimens has been conducted. Based on this study, 16 taxa are currently recognized. We also defined two groups of species that could possibly be treated as distinct sections. To determine whether morphologically defined species and sections could be supported by phylogenetic analyses, we conducted phylogenetic analyses on data derived from six distinct DNA sequences, one nuclear (ITS) and five plastid regions (matK, rps16, trnC-petN, trnL-trnF and ycf1). Preliminary parsimony analyses based on three of these markers (ITS, matK, and trnL-trnF) indicated that Ancistrorhynchus is monophyletic and comprises two well supported subclades. These results accord well with the sectional delimitation based on morphological characters. The first of two main subclades includes species characterized by a spiciform inflorescence, a constricted spur, and a pollinium with a common stipe. The second subclade includes species with a capituliform inflorescence, a straight spur, and two distinct stipites. Agreement between molecular and morphological data was thus clear at the subgeneric level. However, at the specific level, this relationships are only partly resolved.

Broader Impacts:

1 - The New York Botanical Garden, Cullman Program for Molecular Systematics, 2900 Southern Blvd., Bronx, NY, 10458-5126, USA
2 - Missouri Botanical Garden, Africa & Madagascar Department, St. Louis, MO, 63110, USA
3 - Université Libre de Bruxelles, Herbarium et Bibliothèque de Botanique africaine, Bruxelles, Belgium
4 - University of Yaoundé I, Plant Systematic and Ecology Laboratory, Higher Teacher’s Training College, Yaoundé, Cameroon
5 - Institut de Recherche pour le Développement (IRD), Umr AMAP, Montpellier, France
6 - James Cook University, Australian Tropical Herbarium, PO Box 6811, Cairns , QLD, 4870, Australia
7 - New York Botanical Garden, Cullman Program For Molecular Systematics, 2900 Southern Blvd., Bronx, NY, 10458-5126, USA

Keywords:
Ancistrorhynchus
Angraecoids
Congo Basin
Epidendroideae
Orchidaceae
tropical Africa
molecular phylogeny
Taxonomy.

Presentation Type: Oral Paper:Papers for Sections
Session: 48
Location: Elmwood/Riverside Hilton
Date: Wednesday, July 31st, 2013
Time: 3:45 PM
Number: 48009
Abstract ID:421
Candidate for Awards:None