This study is a continuation of our work on other subtribes of the tribe Maxillarieae, especially subtribes Oncidiinae, Stanhopeinae, and Zygopetalinae.
PHYLOGENETICS OF TRIBE MAXILLARIEAE
Although this site is primarily concerned with the subtribe Maxillariinae, we have worked on the other subtribes of the tribe Maxillarieae, as well as on the overall systematics and phylogenetics of the tribe. The monophyly (100% bootstrap support) and subtribal relationships of tribe Maxillarieae were established based on highly resolved, well-supported cladograms of combined ITS, matK, and trnL-F sequence data (Whitten at al. 2000). We recognized six subtribes: Coeliopsidinae, Eriopsidinae, Maxillariinae (including Lycastinae and Bifrenariinae), Oncidiinae (including Pachyphyllinae, Ornithocephalinae, Telipogoninae, and Lockhartiinae), Stanhopeinae, and Zygopetalinae (including Cryptarrheninae, Dichaeinae, Huntleyinae, and Warreinae). These data do not support the taxonomic systems of Brieger et al. (1994-2000) or Szlachetko (1995).
The relationships shown below of subtribes in Maxillarieae are based on the combined ITS/matk/trnL-F analyses. For other subtribes, see Oncidiinae, Stanhopeinae, Zygopetalinae. The relationships in subtribes in
Oncidiinae and Zygopetalinae are also based on the combined ITS/matk/trnL-F analyses.
PHYLOGENETICS OF SUBTRIBE MAXILLARIINAE
Cladograms based on molecular data sets
Phylogenetic relationships within the orchid subtribe Maxillariinae sensu Dressler (1993) with emphasis on Maxillaria
s.l. were inferred using parsimony analyses of individual and combined DNA sequence data. We analyzed nrITS DNA, the plastid matK
gene and flanking trnK
intron, and the plastid atpB-rbcL
intergenic spacer for 619 individuals representing ca. 354 species. The plastid rpoC1
gene (ca. 2600 bp) was sequenced for 84 selected taxa and combined in a more limited analysis (Fig.8 below) with the other data sets to provide greater resolution in the spine of the trees. A well-resolved and supported consensus was found, for which most clades were present in more than one individual analysis. All the currently recognized minor genera of "core" Maxillariinae (Anthosiphon, Chrysocycnis, Cryptocentrum, Cyrtidiorchis, Mormolyca, Pityphyllum
, and Trigonidium
) are embedded within a polyphyletic Maxillaria
s.l. Our results support the recognition of a smaller, more restricted Maxillaria
, of some previously published segregate genera (Brasiliorchis, Camaridium, Christensonella, Heterotaxis, Ornithidium, Sauvetrea
), and of several novel clades at the generic level. These revised monophyletic generic and infrageneric concepts will hopefully minimize further nomenclatural changes, encourage monographic studies, and facilitate more focused analyses of character evolution within Maxillariinae. ABSTRACT
from Whitten, W.M., M. A. Blanco, N. H. Williams, S. Koehler, G. Carnevali, R. B. Singer, L. Endara, & K. M. Neubig. 2007. Molecular Phylogenetics of Maxillaria and Related Genera (Orchidaceae: Cymbidieae) Based Upon Combined Molecular Data Sets. American Journal of Botany
The cladograms below are based on the combined analyses extracted from Whitten, W.M., M. A. Blanco, N. H. Williams, S. Koehler, G. Carnevali, R. B. Singer, L. Endara, & K. M. Neubig. 2007. Molecular Phylogenetics of Maxillaria and Related Genera (Orchidaceae: Cymbidieae) Based Upon Combined Molecular Data Sets. American Journal of Botany
94: 1860-1889. This paper is available as a pdf from the Botanical Society of America web site at http://www.amjbot.org/cgi/reprint/94/11/1860.
Nomenclature has been updated and follows Blanco, M. A. G. Carnevali, W. M. Whitten, R. Singer, S. Koehler, N. H. Williams, I. Ojeda, K. Neubig, & L. Endara. 2007. Generic Realignments in Maxillariinae (Orchidaceae). Lankesteriana
The following cladograms will open in a new window. Because these files are quite large, it takes a few seconds for the image to load. Click to zoom, drag to move image; other controls at bottom. Representative photographs of these clades are shown in the IMAGES section of this site..
Fig.8, Summary cladogram based on nrITS, the plastid matK gene and flanking trnK intron, the plastid atpB-rbcL intergenic spacer, and the plastid rpoC1 gene.
Fig.1, Pityphyllum, Ornithidium, Heterotaxis, Nitidobulbon, and outgroups
Fig.2, Mormolyca, Sauvetrea, Cyrtidiorchis, Cryptocentrum, Inti, Brasiliorchis
Fig.3, Christensonella, Mapinguari
Fig.4, Trigonidium, Maxillariella, Rhetinantha
Fig.6, Maxillaria s.s.
Fig.7, Maxillaria s.s.(continued)
Funding was provided by U.S. National Science Foundation grant No. DEB-0234064 to N. H. Williams and W. M. Whitten for the project Systematics of Maxillariinae (Orchidaceae): Generic delimitation, pollinator rewards, and pollination.
Additional funding was provided by a Furniss Foundation graduate student fellowship from the American Orchid Society to M. A. Blanco and by Kew Latin American Research Fellowships to M. A. Blanco (to study specimens in European herbaria) and to S. Koehler (to study systematics of the Maxillaria madida
alliance). Funding was provided to R. Singer by a FAPESP postdoctoral grant 01/08958-1 and to G. Carnevali from CICY for the project "Orchidaceae Neotropicales".