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We examined the impact of successive alignment quality‐control steps on downstream phylogenomic analyses. We applied a recently published phylogenomics pipeline that was developed for the Angiosperms353 target‐sequence‐capture probe set to the flowering plant order Celastrales. Our final dataset consists of 158 species, including at least one exemplar from all 109 currently recognized Celastrales genera. We performed nine quality‐control steps and compared the inferred resolution, branch support, and topological congruence of the inferred gene and species trees with those generated after each of the first six steps. We describe and justify each of our quality‐control steps, including manual masking, in detail so that they may be readily applied to other lineages. We found that highly supported clades could generally be relied upon even if stringent orthology and alignment quality‐control measures had not been applied. But separate instances were identified, for both concatenation and coalescence, wherein a clade was highly supported before manual masking but then subsequently contradicted. These results are generally reassuring for broad‐scale analyses that use phylogenomics pipelines, but also indicate that we cannot rely exclusively on these analyses to conclude how challenging phylogenetic problems are best resolved. [ABSTRACT FROM AUTHOR]

Based on a recent collection, we present the rediscovery of Peperomia crypticola C. DC., a rare species only known from eastern Minas Gerais, Southeastern Brazil. This species was now found in western Rio de Janeiro, more than 200 km apart and more than hundred years after the original description. An emended description, distribution map, color photographs of the fresh collection and comparison of the species with the closely related Peperomia lanceolatopeltata C. DC. are presented. [ABSTRACT FROM AUTHOR]

We report the first record of Oziroë argentinensis (Asparagaceae) for Brazil, previously known from Paraguay, Bolivia, and Argentina. The plant was collected in the state of Mato Grosso do Sul, growing between limestone rocks, and is the first record of any species of Oziroë on this substrate. [ABSTRACT FROM AUTHOR]

Widespread in the tropics, Cissus includes more than 300 species with great morphological diversity. Of the 78 species found in the New World, 64 grow in South America. This paper investigates phylogenetic relationships within Cissus, focusing on the South American species, insufficiently sampled in previous studies. Both plastid (trnL intron, trnL-F intergenic spacer, rpsl6) and nuclear ribosomal internal transcribed spacer (ITS) DNA sequences were analyzed with parsimony, likelihood and Bayesian inference. Divergence times were estimated with relaxed-clock Bayesian molecular dating. The evolution of leaf shape was reconstructed using parsimony. South American Cissus is resolved as not monophyletic. It consists of three clades: Cissus striata, Cissus trianae, and core Cissus. A clear separation between the Cissus striata clade and the other Cissus species was observed based on molecular and morphological characters. The relationship between the only species of the Cissus trianae clade and those of core Cissus is not clarified by our data. The geographic disjunction between the New and Old World taxa of core Cissus was estimated to have originated in the Late Eocene, and diversification in the Americas started in the Oligocene. In spite of the plasticity of leaf shape within species or individuals, this character is considered useful for infrageneric classification. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of two concentrations of copper (0.13 and 0.5 mg L−1) on juveniles of tilapia, Oreocromis niloticus (Linnaeus), using two toxicological assays (I- copper exposure and II- copper exposure followed by recovery). Doses were taken from the liver of the test organisms to determine the concentrations of copper, reduced glutathione, activities of glutathione S-transferase and catalase, and lipid peroxidation. Exposure to copper in both assays resulted in significant accumulation of this metal in the analysed tissue and in decreased concentration of reduced glutathione. There was no alteration in the activities of catalase and glutathione S-transferase and in lipid peroxidation. [ABSTRACT FROM AUTHOR]

This paper describes three new species of Salacioideae Cheiloclinium and Salacia (Celastraceae) from South America: C. brevipetiolatum Lombardi is characterized by its very short, only 5 mm long petioles; S. krigsneri Lombardi is distinguished by its dichasium (inflorescence) with shortened lateral branches, a unique feature among neotropical species; and S. vernicosa Lombardi can be discerned from other species by its fascicled inflorescences and large leaves, dried inflorescence covered with resinous substance, tubuliform flowers, flat, ring-shaped disc, and berries with ribs at base and lobes at apex. [ABSTRACT FROM AUTHOR]