We present novelties in Thismiaceae for the south of the Brazilian Amazon, resulting from botanical expeditions in the north of the Mato Grosso State. The occurrence of four species is recorded: Thismia hyalina; T. melanomitra; T. singeri and a species new to science: T. ribeiroi. These are the first records of the family Thismiaceae, as well as of the genus Thismia and these species for the Mato Grosso State. Thismia melanomitra is a new species for the flora of Brazil and T. singeri is the second record of the species for Brazil. In this study, we also describe and illustrate the new species Thismia ribeiroi.

The Neotropical genera Aspidogyne and Microchilus (Goodyerinae, Cranichideae, Orchidaceae) comprise ca. 200 rainforests terrestrial species. Although species of Goodyerinae are described with similar anatomy to other taxa of Cranichideae, some anatomical characteristics appear to be specific to the subtribe. Our goal was to characterise the anatomical structure of the vegetative organs of Aspidogyne and Microchilus to identify specific characters of Goodyerinae. Root, stem and leaf samples from eleven species were analysed using light and scanning electron microscopy. The leaves are hypostomatic and glabrous with predominantly anisocytic or tetracytic stomata, thin cuticle, homogeneous mesophyll with chromoplast and raphides, and collateral vascular bundles with parenchyma sheath and collenchyma in the midrib. Spiranthosomes were cofirmed for all species and some specific characteristics were identified in the root, such as the presence of collenchyma in both the cortex and the stele, vascular tissue with fibre-tracheids in the centre of the vascular cylinder, and the presence of a true endodermis with Casparian strips in the stem. Therefore, the root and stem were the organs that showed more taxon-specific characteristics for Goodyerinae, which can be used to better delimited the subtribe.

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Thismia singeri, is described for the first time for Brazil, being the first record of this family for Para Śtate and the third record for this rare species in nature. In Para ´state, northern Brazil, this species was found growing in Itaituba municipality near the River Tapajo ´s, in a well preserved submontane rain forest with a dense canopy. Due to the holotype is incomplete, we provide a more comprehensive description for this species based on complete individuals, thus clarifying some aspects of its morphology such as the parietal placenta, the root system, and tepal morphology. This is the second species of Thismiaceae described for Amazonia. Thismia hyalina, the other Amazonian species, is easily distinguished from T. singeri by its tubers, leaves inserted just below the flower, the latter with two tepal whorls, the upper one clawed, reniform and erect, and the lower one linear triangular.

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.