LUER (2000) used the following characters as rapid identifiers for diagnosing subgenera, sections and subsections within Masdevallia (Table 15): peduncle terete or triquetrous, anthesis of the flowers (whether the flowers are opening either successively or simultaneously), type of floral bract, the ovary smooth or with some external features such as crests or papillae, the grade of connation between the sepals, the free portion of the apex of the sepals produced into tails, the callus from the labellar margin ending in a process, and the lip divided into an epichile and a hypochile.
Table 15 Rapid identifier for subgenera and sections according to Luer (2000) Subgenera/Section Peduncle Raceme Floral
bract Ovary Connation of sepals
Sepaline tails
Process of petals
Lip divided
Subgen. Amanda Terete Simul. Infl. + + + 0, mostly
serrate +
Subgen. Cucullatia Terete 1-fl. Infl. + + + 0, tip
verrucose +
Subgen. Fissia Terete 1-fl. - + Free + 0 + +
Subgen. Masdevallia
Sect. Amaluzae Terete Succ. - + 0 + + 0 0
Sect. Coriaceae Terete 1-fl. - - + + 0 + 0
Sect. Durae Terete Succ. - - + + 0 0
Sect. Dentatae Terete Succ. - - + + + 0
Sect. Masdevallia Terete 1-fl. - - + + + 0
Sect. Minutae Terete 1, simul,
Succ. - - + + + pointed 0
Sect. Racemosae Terete Simul. - - + 0 0 0
Sect. Reichenbachianae Terete 1, succ. - - + + 0 0
Sect. Triotosiphon Terete 1-fl. - - + + 0 0
Subgen. Meleagris Terete Succ. - + Free + 0 0
Subgen. Nidificia Terete 1-fl. - + + + + +
Subgen. Polyantha
Sect. Alaticaules Triquetrous Succ. - - + + + 0 +
Sect. Polyanthae Terete 1, simul,
Succ. - - + + 0 +
Subgen. Pygmaeia
Sect. Aphanes Terete 1, succ. - + + + 0 0 0
Sect. Pygmaeae Terete 1, succ. - + + + + 0
Subgen. Scabripes Scabrous Succ. - - + + + 0
Subgen. Volvula Terete 1-fl. - - + + 0 +
Key: terete = round in cross section; triquetrous= triangular in cross section; 1-fl. = peduncle single-flowered; simul. = raceme simultaneously flowered; succ. = raceme successively flowered; infl. = inflated; - = not remarkable; for ovaries, +
= carinate, lamellate, or verrucose; for sepals and petals, + = tail or tooth present, 0 = absent; for lip, + = lip divided by marginal folds into an epichile and hypochile, 0 = lip not divided by marginal folds in two parts.
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The polarity or probable direction of the evolution of the rapid identifier characters was not discussed.
To evaluate their phylogenetic significance, we reconstructed their distribution on the strict consensus from the analysis of the molecular data.
Peduncle – Fig. 85 shows the most parsimonious derivation of the character ‘peduncle triquetrous in cross section’. Peduncles triquetrous in cross section have been used as one of the most important characters for diagnosing all interrelated species of subgenus Polyantha. According to LUER (2000), four species of this large subgenus produce both, terete and triangular peduncles (M. garciae Luer, M. infracta Lindl., M. richarsoniana Luer, and M. sprucei Rchb. f.). The results of the molecular analysis suggest a non-monophyletic subgenus Polyantha. Its species are found in a clade mixed with species of subgenus Masdevallia sections Minutae, Reichenbachianae, and Dentatae and species of subgenus Pygmaeia sections Amaluzae and Aphanes. The reconstruction of the peduncle in cross section in one of the most parsimonious trees obtained from the analysis of molecular data shows a triquetrous peduncle in some members of subclade B2 derived from a terete peduncle. The data do not allow to decide with certainty whether this character had a single origin or not.
Fig. 85 Reconstruction of character state evolution of the peduncle in cross section optimized on one of the MPTs derived from the ITS sequences data analysis for Masdevallia.
Raceme – Flowers opening either successively or simultaneously have been used to characterize some infrageneric taxa (Table 15). Flowers opening successively in periodic clusters has evolved 3-4 times within the genus (Fig. 86): once in subgenus Amanda and M. nidifica (clade D), once in M. schlimii (clade B), and once or twice in clade C3.
Fig. 86 Reconstruction of character state evolution of the peduncle in cross section optimized on one of the MPTs derived from the ITS sequences data analysis for Masdevallia.
Floral bract – Fig. 75 shows the most parsimonious derivation of the type of floral bract. An inflated floral bract has evolved at least twice, once in subclade D4, with a reversal in M. molossus and M. ophioglossa, and once in M. picturata (subclade D3). A cucullate floral bract has evolved twice within the genus, once in subclade D1, with a reversal in M. teaguei, and once in M. macrura. This latter species was previously included within subgenus Cucullatia based on this character and later transferred to section Coriaceae. The molecular analysis does not support the inclusion of this species neither in subgenus Cucullatia, nor in section Coriaceae.
Ovary – Species with the ovaries with ribs manifested by crests or some other external features such as papillae or lamella are characteristic for subgenera Amanda, Cucullatia, Fissia, Nidificia, Meleagris, and Pygmaeia (Table 15). An ovary with undulating crests is reconstructed as having been derived four times within the genus Masdevallia, once in M. hoeijeri, once in M. caudivolvula, once in M. corniculata, and once in subclades D2, D3, and D4 (Fig. 64).
Connation of the sepals – According to LUER (2000) the subgenera Fissia and Meleagris can be characterized by a dorsal sepal that is free from the lateral (Table 15). This character has evolved at least once within the genus Masdevallia, in subgenus Meleagris (subclade D2) and subgenus Fissia (subclade D3) (Fig. 65). These subgenera form an unresolved trichotomy with subgenus Meleagris.
Sepaline tails – The free portion of the apex produced into tails has been used as rapid identifier for subgenera and sections of Masdevallia (Table 15). Tailless flowers characterize subgenus Pygmaeia
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section Aphanes. Some species of subgenus Fissia and subgenus Masdevallia section Coriaceae are characterized by tailless sepals. The sepaline tails apparently have been lost several times within Masdevallia (Fig. 87).
Fig. 87 Reconstruction of character state evolution of the apices of the sepals optimized on one of the MPTs derived from the ITS sequences data analysis for Masdevallia.
Petal tails – According to LUER (2000) a callus from the labellar margin ending in a process is characteristic for the subgenera Fissia, and Nidificia, subgenus Masdevallia sections Masdevallia and Dentatae, subgenus Polyantha section Alaticaules, subgenus Pygmaeia section Pygmaeae, and subgenus Scabripes. A callus ending in an acute and retrorse (uncinate) process near the base characterizes subgenus Masdevallia section Masdevallia (LUER 2000). Figure 88 shows that this character originated repeatedly and revested at least occasionally. Therefore, it appears not to be phylogenetically useful at the infrageneric level. A callus ending in an obtuse angle between the middle and the lower third characterizes subgenus Masdevallia section Coriaceae (LUER, 2000).
Figure 88 shows this character as synapomorphy for subclades B2 and B3. However it shows many reversals and cannot be considered phylogenetically useful and the infrageneric level. A callus ending in a broad and rounded process characterizes some species of subgenus Polyantha sections Alaticaules and Coaetanae (LUER 2000). Figure 88 shows that this character is very homoplasious and not useful at the infrageneric level.
Fig. 88 Reconstruction of character state evolution of the callus of the petals optimized on one of the MPTs derived from the ITS sequences data analysis for Masdevallia.
Lip – Subgenera Amanda, Cucullatia, Fissia, Nidificia, Polyantha, and Volvula are characterized by a lip that is divided by marginal folds into an epichile and hypochile (LUER, 2000). Entire lips (not divided into an epichile and a hypochile) characterize species of subgenera Masdevallia and Pygmaeia. A lip that is divided by marginal folds into an epichile an a hypochile has evolved at least five times in the genus Masdevallia, once in subclade B2, with a reversal in a subclade comprising M. vieirana, M. zahlbrucknerii, and M. naranjapatae, in the subclade of M. fulvescens and M. reichenbachiana, as well as in M. scabrilinguis, M. chimboensis, M. mentosa, and M. collina. In addition, it originated in M. gutierrezii and M. bicornis, and (equivocally) in subclade C2 and clade D (Fig 53).
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