Aims:  Cyanobacteria‐deprived lichens of the species Canoparmelia caroliniana, Canoparmelia crozalsiana, Canoparmelia texana, Parmotrema sancti‐angeli and Parmotrema tinctorum were screened for the presence of chemo‐organotrophic nitrogen‐fixing bacteria. Methods and Results:  Fifty‐three lichen samples subjected to enrichment selection using a nitrogen‐free minimal medium were positive for acetylene reduction. Seventeen isolates, able to fix nitrogen, belonged to Gamma‐proteobacteria group and were identified as: Acinetobacter sp., Pantoea sp., Pseudomonas sp., Pseudomonas stutzeri, Serratia marcescens and Stenotrophomonas maltophilia, according to 16S rRNA gene sequences and biochemical tests. The excretion of amino acid and phytohormone and the ability of mineral phosphate solubilization were determined in 14 isolates. All isolates were able to release amino acids and 3‐indoleacetic acid. About 64% of the isolates solubilized phosphates and 30% released ethylene. Conclusions:  These data confirm sparse evidence from the literature on the occurrence of chemo‐organotrophic nitrogen‐fixing bacteria in cyanobacteria‐deprived lichens; the isolates presented physiologic features which might benefit the host if they are expressed when the bacteria are harboured by lichens. Significance and Impact of the Study:  Chemo‐organotrophic nitrogen‐fixing bacteria were isolated from a high percentage (72·6%) of cyanobacteria‐deprived lichens. All isolates presented important physiological characteristics, some of which are being described here for the first time.

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De larvas e pupas de Musca domestica, Chrysomya albiceps, Cochliomyia homivorax, Stomoxys calcitrans e Syntesiomyia nudiseta coletadas em diversos ambiente, em São Paulo, Paraná, Mato Grosso, Mato Grosso do Sul e Minas Gerais, foram obtidas dez espécies de microhimenópteros parasitóides da supermamília Chalcidoidea, algumas assinaladas pela primeira vez no Brasil

Fourteen strains of nitrogen-fixing bacteria were isolated from different agricultural plant species, including cassava, maize and sugarcane, using nitrogen-deprived selective isolation conditions. Ability to fix nitrogen was verified by the acetylene reduction assay. All potentially nitrogen-fixing strains tested showed positive hybridization signals with a nifH probe derived from Azospirillum brasilense. The strains were characterized by RAPD, ARDRA and 16S rDNA sequence analysis. RAPD analyses revealed 8 unique genotypes, the remaining 6 strains clustered into 3 RAPD groups, suggesting a clonal origin. ARDRA and 16S rDNA sequence analyses allowed the assignment of 13 strains to known groups of nitrogen-fixing bacteria, including organisms from the genera Azospirillum, Herbaspirillum, Pseudomonas and Enterobacteriaceae. Two strains were classified as Stenotrophomonas ssp. Molecular identification results from 16S rDNA analyses were also corroborated by morphological and biochemical data.