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 on combined molecular data sets. Amer. J. Bot. 94:1860-1889.

Abstract. The orchid genus Maxillaria is one of the largest and most common of neotropical orchid genera, but its current generic boundaries and relationships have long been regarded as artificial. Phylogenetic relationships within 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 a combined matrix of 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 species and combined in a more limited analysis with the other data sets to provide greater resolution. In a well-resolved, supported consensus, 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 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 concepts should minimize further nomenclatural changes, encourage monographic studies, and facilitate more focused analyses of character evolution within Maxillariinae.

Key Words. atpB-rbcL spacer, matK, Maxillaria, Maxillariinae, molecular phylogenetics, nrITS, Orchidaceae, rpoC1

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Blanco. M.A., G. Carnevali, W.M. Whitten, R.B. Singer, S. Koehler, N.H. Williams, I. Ojeda, K. Neubig & L. Endara. 2008. Generic realignments in Maxillariinae (Orchidaceae). Lankesteriana 7(3): 515 - 537.

Abstract. A recent phylogenetic analysis of four DNA regions for ca. 354 species of core Maxillariinae strongly indicate that the genus Maxillaria, as traditionally circumscribed, is grossly polyphyletic. We present a new phylogenetic classification for core Maxillariinae that recognizes 17 genera. Necessary realignments include: 1) resurrection of the genera Camaridium, Heterotaxis, and Ornithidium; 2) recognition of the recent segregates Brasiliorchis (=Maxillaria sect. Repentes), Christensonella (=Maxillaria sect. Urceolatae), Nitidobulbon (in press), and a recircumscribed Sauvetrea (=Maxillaria sect. Trigonae); 3) adoption of the new genera Inti (=Maxillaria sect. Polyphyllae), Mapinguari, Maxillariella (=Maxillaria sections Ebulbes and Erectae), and Rhetinantha; 4) transfers from Maxillaria sect. Reflexae to Ornithidium, and Maxillaria sect. Rufescens to Mormolyca; and 5) synonymizing of the genera Adamanthus, Pseudomaxillaria, Psittacoglossum, and Sepalosaccus (under Camaridium), Anthosiphon (under Cryptocentrum), Chrysocycnis (under Mormolyca), Dicrypta, Marsupiaria, and Pentulops (under Heterotaxis), and Laricorchis, Neo-urbania, and Siagonanthus (under Ornithidium). Some new synonyms at the specific level are also presented.

Resumen. Un reciente análisis filogenético de cuatro regiones de ADN para ca. 354 especies de la subtribu Maxillariinae indican fuertemente que el género Maxillaria, en su circunscripción tradicional, es altamente polifilético. Presentamos una nueva clasificación filogenética para Maxillariinae que reconoce 17 géneros. Los cambios necesarios incluyen: 1) la resurrección de los géneros Camaridium, Heterotaxis, y Ornithidium; 2) el reconocimiento de los recientes segregados genéricos Brasiliorchis (=Maxillaria sección Repentes), Christensonella (=Maxillaria sección Urceolatae), Nitidobulbon (en prensa), y una Sauvetrea recircunscrita (=Maxillaria sección Trigonae); 3) la adopción de los nuevos géneros Inti (=Maxillaria sección Polyphyllae), Mapinguari, Maxillariella (=Maxillaria secciones Ebulbes y Erectae), y Rhetinantha; 4) transferencias de Maxillaria sección Reflexae a Ornithidium, y Maxillaria sección Rufescens a Mormolyca; y 5) puesta en sinonimia de los géneros Adamanthus, Pseudomaxillaria, Psittacoglossum y Sepalosaccus (bajo Camaridium), Anthosiphon (bajo Cryptocentrum), Chrysocycnis (bajo Mormolyca), Dicrypta, Marsupiaria y Pentulops (bajo Heterotaxis), y Laricorchis, Neo-Urbania, y Siagonanthus (bajo Ornithidium). Algunos sinónimos nuevos al nivel de especie también son presentados.

Key Words. Cymbidieae, generic recircumscription, Inti, Mapinguari, Maxillariella, Maxillariinae, Orchidaceae, Rhetinantha.

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Atwood, J.T. 1995. Two Overlooked Species of Maxillaria from Central America. Selbyana 16(2): 242-245.

Abstract. Two new species of Maxillaria from Costa Rica are described to validate names for use in each of several regional floras. The first species treated, M. chionantha (also widespread in Panama), is related to M. pachyacron Schltr. but the leaves are broader, the flowers are somewhat smaller and entirely white. The second species, M. haberi, is best compared to M. planicola C.Schweinf., but the pseudobulbs are subtended by at least one foliaceous bract, and the lip has a 3-carinate callus unlike the ligulate callus with furcate trichomes of the latter species.

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