The jewel orchids (Goodyerinae), named after their often colourful leaves, have a pantropical distribution with a clear Asian centre of diversity. However, the Nearctic and Neotropical America together form a second centre of diversity, with one-third of known species of Goodyerinae. Previously, only a few American samples have been included in phylogenetic studies, and their putatively Asian origins and American divergence times were poorly known. To elucidate these topics, we inferred phylogenetic trees, performed molecular dating and reconstructed biogeographic history using nuclear ribosomal ITS and plastid matK sequences for 34 species of Goodyerinae from the New World and 76 previously published accessions of Cranichideae. Our well-supported phylogenetic topology suggests two independent dispersal events to the New World from the Indomalesian region during the Miocene. The first inferred dispersal of a Neotropical clade diverged c. 11 Mya from their most recent common ancestor (MRCA), comprising three highly supported subclades that do not match the limits of Aspidogyne, Kreodanthus and Microchilus as previously circumscribed. The second dispersal involved a largely Nearctic clade of Goodyera s.l. diverging c. 8.4 Mya from the MRCA and exhibiting a complex biogeographic history with subsequent dispersals between the Nearctic and Indomalesia. The occurrence of these species in gallery forests putatively prevented vicariance events imposed by the expansion of the Chacoan region as previously detected for epiphytic Orchidaceae. Eighty-nine nomenclatural combinations and three new names in Microchilus are proposed.

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Pabstiella consists of c. 130 epiphytic species in the Neotropics. We present a phylogenetic analysis based on nrITS, matK and trnH-psbA sequences from 59 species of the genus and 40 Pleurothallidinae and two Laeliinae and one Bletiinae as an outgroup, using maximum likelihood, Bayesian inference and maximum parsimony. We also performed molecular dating, biogeographical analyses and ancestral morphological character reconstruction. Our results confirm the monophyly of Pabstiella with strong support. Ten clades are inferred and are herein proposed as sections. Pabstiella originated in the Andes and the Atlantic Rainforest in the Late Miocene (c. 7.93 Mya) in an epoch when these biomes were probably connected. A main vicariance event divided an early-diverging lineage that inhabited the Andes from an Atlantic Rainforest lineage that diversified in this region during the Pliocene and Pleistocene, mainly in the Serra do Mar in south-eastern Brazil. Our findings also suggest that the Atlantic Rainforest may have played an important role in the origin of subtribe Pleurothallidinae. The morphological character reconstruction showed high levels of homoplasy, with few recognized synapomorphies associated with stems and petals. Other characters related to the habit and stems were identified as important in the evolutionary history of the genus.

In order to evaluate the monophyly of the genus Orleanesia (Orchidaceae) and to assess its position within Laeliinae, a phylogenetic analysis was performed using molecular (nuclear ITS and plastid matK DNA sequences) and morphological data. A taxonomic revision of Orleanesia was also performed, with a description of the genus and its species using fresh living plants and 115 exsiccates from 31 herbaria. All phylogenetic analyses were highly congruent, and thus the sequence data from all three data sets were combined. The resulting phylogeny corroborated the monophyly of Orleanesia, with two strongly supported clades, and confirmed Caularthron as its sister group. Character analysis was not very informative due to a high degree of homoplasy. Two lectotypifications and three new synonyms were proposed for the genus, thereby reducing the number of accepted species to six. Although none of the species of Orleanesia are considered endangered, it is clear that some populations are threatened with deforestation and habitat reduction.

Dryadella (Orchidaceae, Epidendreae) is a Neotropical genus predominantly distributed in the Andean region and the Atlantic rainforest (ARF). Three species occurring in the Brazilian ARF, Dryadella edwallii, D. wuerstlei, and D. zebrina, are challenge to tell apart due to the overlap of morphological characters that define them, so we considered these species as morphotypes. To evaluate the current taxonomic status and to identify suitable characters for the better delimitation of taxon within this group, we measured and analyzed 40 flower characters from 145 individuals of 23 populations distributed throughout the geographical range of this species complex, representing all the morphological diversity of these morphotypes. We performed a principal component analysis (PCA) to summarize all the morphological variations found and a permutational multivariate analysis of variance (PERMANOVA) to verify whether the groups formed by the PCA are statistically different. To assess the phenetic relationships among individuals, we generated an unweighted pair group method with arithmetic mean (UPGMA) dendrogram. As a result, it was possible to clearly differentiate D. wuerstlei from the two other species. The variables that contributed most to the differentiation of the species were the perimeter and area of the sepals (SD1, SD2, SL10); area and width of the apex, mid-portion, and base of the petals (PT19, PT21, PT22, and PT2); and the measurements of the base and widest portion of the lip blade (LB36, LB38). The second group was formed by all individuals of D. edwallii and D. zebrina which present highly overlapping characters with no clear separation between their populations based on PCA and UPGMA results. With this in view, we considered that D. edwallii and D. zebrina correspond to a single species, while D. wuerstlei should remain recognized as a distinct species. We present a taxonomic circumscription of D. wuerstlei and D. zebrina to clarify the taxonomic delimitation of these taxa, highlighting morphological diagnostic characters and their geographical distribution.

Abstract— Even though the monophyly of the Ornithocephalus clade (Oncidiinae) is currently well defined, the systematic positioning of Centroglossa and Dunstervillea remains obscure in the clade due to the absence in previous phylogenetic studies. Centroglossa has a very similar habit and is indistinguishable from Zygostates, whereas Dunstervillea has as its main characteristic the calcarate labellum, also found in Centroglossa. We clarify the systematic and phylogenetic positioning of Centroglossa and Dunstervillea in the Ornithocephalus clade (OC) through analysis of maximum likelihood, Bayesian inference, and maximum parsimony from molecular data (nrITS and matK cpDNA) and morphology. Our results indicate that Dunstervillea is phylogenetically close to Eloyella; both genera have a psigmoid habit, single-sided and flattened leaves, floral perianth with the same coloring, petals with entire margins, and a short rostellum. Centroglossa appears as a subclade within Zygostates. In addition to several homoplastic features, these two genera have the dorsal position of viscidium as a synapomorphy. The calcarate labellum, common to Centroglossa and Dunstervillea, originated more than once in the OC. Based on the phylogenetic results, we propose the nomenclatural changes to include Dunstervillea in Eloyella and Centroglossa in Zygostates. New synonyms are indicated to Zygostates greeniana and Z. nunes-limae and lectotypes are indicated to Centroglossa macroceras and C. glaziovii.

Habitat selection has long been a central theme in ecology and has historically considered both physiological responses and ecological factors affecting species establishment. Investigating habitat selection patterns at different scales can provide important information on the relative roles of the environmental factors influencing the organisms’ abilities to use their surrounding habitat. This work aimed at investigating which environmental factors determine habitat selection by Rhinella icterica tadpoles, and also took the opportunity to investigate how the scale in which tadpoles and environmental data are sampled might influence the habitat selection results. A total of 2.240 tadpoles were counted in the whole sampling area, and while substrate cover and depth were the variables that better explained the abundance of tadpoles at the larger scale (plot level), depth and water turbidity better explained tadpoles’ abundance at the smaller scale (subplot level). The results suggest that avoiding predation by matching the background color is a likely process explaining tadpoles’ occupancy at both scales. Depth is known to influence tadpole habitat use in the tropics, and although its combination with turbidity and substrate cover varied between scales, our study suggests that sampling at different scales might not affect the inferred ecological processes driving habitat selection. This information might also be useful to predict tadpoles’ responses to micro-environmental perturbations and help in guiding the choice of parameters that should be taken into account when analyzing the effects of habitat degradation in Atlantic Forest amphibian populations.