@ARTICLE{TreeBASE2Ref18595,
author = {Aaron H. Kennedy and L. E. Watson},
title = {Species Delimitations and Phylogenetic Relationships within in the Fully Myco-heterotrophic Hexalectris (Orchidaceae)},
year = {2010},
keywords = {},
doi = {10.1600/036364410790862489},
url = {},
pmid = {},
journal = {Systematic Botany},
volume = {35},
number = {1},
pages = {64--76},
abstract = {Phylogenetic analyses were conducted using six plastid markers and the ITS from 43 accessions representing all eight currently recognized Hexalectris species with the goals of testing species circumscriptions and determining interspecific relationships. The monophyly of H. warnockii, H. grandiflora, H. brevicaulis, and H. nitida, plus the H. spicata species complex, are strongly supported. The remaining species are not monophyletic, prompting the recircumscription of H. spicata s.l. as H. spicata s.s. and H. arizonica, H. revoluta s.l. as H. revoluta s.s. and H. colemanii, and H. fallax as a synonym of H. parviflora. Four major morphologically distinct lineages exist within the genus: H. warnockii, H. grandiflora, H. brevicaulis, H. spicata species complex. Within the latter, only H. spicata s.s. and H. nitida are strongly supported as sister species among all trees and the positions of H. revoluta s.s. and H. parviflora remain unresolved due to incongruence in the plastid trees when psbA is included or excluded from analyses. Incongruence between the plastid and ITS topologies was restricted to the positions of H. colemanii and H. arizonica, which suggests that either one or both of these species are of hybrid origin or that the ITS topology has been influenced by incomplete lineage sorting.}
}