No abstract

After discovering an unknown Euphorbiaceae with an unusual combination of morphological characters, molecular phylogenetic analyses were conducted to evaluate the phylogenetic position of the plant. Results of the analyses support the recognition of a resolved lineage sister to a clade comprising Caryodendron, which is sister to the Adenophaedra + Bernardia clade in subfamily Acalyphoideae. The phylogenetic position of this taxon is also supported by morphology, justifying the description of a new genus and species, Bahiana pyriformis, from the Caatinga seasonally dry forest, in Bahia State, Brazil. We compare morphological characters and discuss the phylogenetic relationships of these four genera, here treated as the Bernardia clade, as well as the possible relationship this clade has with genus Avellanita and tribe Plukenetieae.

Although inselbergs from around the world are iconic ecosystems, little is known on the underlying mechanisms of community assembly, especially in their characteristic patchy outcrop vegetation. Environmental constraints are expected to cause phylogenetic clustering when ecological niches are conserved within evolutionary lineages. We tested whether vegetation patches from rock outcrops of the Piedra La Tortuga Natural Monument, in the northern Amazon region, are phylogenetically clustered, indicating that environmental filtering is the dominant driver of community assemblage therein. We classified all patches according to their size as very small (< 1 m2), small (1-4 m2), medium-sized (4-8 m2), and large patches (8-15 m2). From each class, we randomly selected 10 patches, totalizing 40 patches covering 226 m2. All individuals found in the 40 isolated patches were identified to the species level. We also correlated measurements of phylogenetic community structure with patch size. We found that species from patches are restricted to the clades monocots, fabids, malvids, and lamiids. We conclude that vegetation in this rock outcrop is phylogenetically clustered. Furthermore, we found that phylogenetic turnover between pairs of patches increases with patch size, which is consistent with a scenario of higher environmental stress in smaller patches. Further research is necessary to identify nurse species in inselberg vegetation, which is pivotal for conservation and restoration of this particular ecosystem.

In the present study, we report 46 new records of vascular plants species from Panama. The species belong to the following families: Anacardiaceae, Apocynaceae, Aquifoliaceae, Araceae, Bignoniaceae, Burseraceae, Caryocaraceae, Celastraceae, Chrysobalanaceae, Cucurbitaceae, Erythroxylaceae, Euphorbiaceae, Fabaceae, Gentianaceae, Lacistemataceae, Lauraceae, Malpighiaceae, Malvaceae, Marattiaceae, Melastomataceae, Moraceae, Myrtaceae, Ochnaceae, Orchidaceae, Passifloraceae, Peraceae, Poaceae, Portulacaceae, Ranunculaceae, Salicaceae, Sapindaceae, Sapotaceae, Solanaceae, and Violaceae. Additionally, the status of plant collections in Panama is discussed; we focused on the areas where we identified significant information gaps regarding real assessments of plant biodiversity in the country.