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Size, dry weight and RNA/DNA measurements of 3876 cod larvae from 26 different families of recruit and repeat spawners reared in two mesocosms ( 2500m³ and 4400m³) under natural conditions were analysed. To be able to relate individual data to parental background, DNA microsatellite analysis was performed. The larvae from the two groups (recruit, repeat) already differed significantly in size and weight at hatching with the larvae from the recruit spawners being larger and heavier at the start of the experiment. Growth curves fitted for the larvae from the recruit spawning groups showed a trend of greater sizes at given ages. For all sampling dates offspring of recruit spawners had significantly higher sizes and dry weights than the repeat spawners. RNA/DNA ratios from recruit spawners showed a trend to higher ratios compared to the repeat spawners. The 2500m³ mesocosm was characterized by low plankton density during the transition from exogenous to endogenous feeding followed by a higher density during the metamorphosis period, while the 4400m³ mesocosm showed the opposite situation. The change in the food density occurring in the mesocosm was reflected in the growth rates. Survival was slightly higher in the mesocosm with the higher food density in the beginning, survival between recruit and repeat is assumed to be the same. Estimates of non-parametric probability distributions of the RNA/DNA ratios differed in the amount of scatter (variability) between mesocosms indicating that the higher food density lead to more better conditioned and fewer badly growing extremes of individual larvae in the first three weeks. When the feeding conditions changed the larvae from the low food environment could compensate and reach similar conditions, but were lacking some of the bad conditioned extremes. RNA/DNA analysis within each mesocosm showed that the individual fish exhibited very different growth and condition responses under the same environmental conditions. These different growth responses in both mesocosms were not related to being offspring of first or recruit spawners but seem to be caused by the environmental conditions.

© 2016 The Author(s). Halorubrum lacusprofundi is an extreme halophile within the archaeal phylum Euryarchaeota. The type strain ACAM 34 was isolated from Deep Lake, Antarctica. H. lacusprofundi is of phylogenetic interest because it is distantly related to the haloarchaea that have previously been sequenced. It is also of interest because of its psychrotolerance. We report here the complete genome sequence of H. lacusprofundi type strain ACAM 34 and its annotation. This genome is part of a 2006 Joint Genome Institute Community Sequencing Program project to sequence genomes of diverse Archaea.

© 2016 The Author(s). Thioalkalimicrobium cyclicum Sorokin et al. 2002 is a member of the family Piscirickettsiaceae in the order Thiotrichales. The γ-proteobacterium belongs to the colourless sulfur-oxidizing bacteria isolated from saline soda lakes with stable alkaline pH, such as Lake Mono (California) and Soap Lake (Washington State). Strain ALM 1Tis characterized by its adaptation to life in the oxic/anoxic interface towards the less saline aerobic waters (mixolimnion) of the stable stratified alkaline salt lakes. Strain ALM 1Tis the first representative of the genus Thioalkalimicrobium whose genome sequence has been deciphered and the fourth genome sequence of a type strain of the Piscirickettsiaceae to be published. The 1,932,455 bp long chromosome with its 1,684 protein-coding and 50 RNA genes was sequenced as part of the DOE Joint Genome Institute Community Sequencing Program (CSP) 2008.

Understanding the key drivers of population connectivity in the marine environment is essential for the effective management of natural resources. Although several different approaches to evaluating connectivity have been used, they are rarely integrated quantitatively. Here, we use a ‘seascape genetics’ approach, by combining oceanographic modelling and microsatellite analyses, to understand the dominant influences on the population genetic structure of two Antarctic fishes with contrasting life histories, Champsocephalus gunnari and Notothenia rossii. The close accord between the model projections and empirical genetic structure demonstrated that passive dispersal during the planktonic early life stages is the dominant influence on patterns and extent of genetic structuring in both species. The shorter planktonic phase of C. gunnari restricts direct transport of larvae between distant populations, leading to stronger regional differentiation. By contrast, geographic distance did not affect differentiation in N. rossii, whose longer larval period promotes long-distance dispersal. Interannual variability in oceanographic flows strongly influenced the projected genetic structure, suggesting that shifts in circulation patterns due to climate change are likely to impact future genetic connectivity and opportunities for local adaptation, resilience and recovery from perturbations. Further development of realistic climate models is required to fully assess such potential impacts.

© 2014 Scheuner et al.; licensee BioMed Central Ltd. Planctomyces brasiliensis Schlesner 1990 belongs to the order Planctomycetales, which differs from other bacterial taxa by several distinctive features such as internal cell compartmentalization, multiplication by forming buds directly from the spherical, ovoid or pear-shaped mother cell and a cell wall consisting of a proteinaceous layer rather than a peptidoglycan layer. The first strains of P. brasiliensis, including the type strain IFAM 1448T, were isolated from a water sample of Lagoa Vermelha, a salt pit near Rio de Janeiro, Brasil. This is the second completed genome sequence of a type strain of the genus Planctomyces to be published and the sixth type strain genome sequence from the family Planctomycetaceae. The 6,006,602 bp long genome with its 4,811 protein-coding and 54 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. Phylogenomic analyses indicate that the classification within the Planctomycetaceae is partially in conflict with its evolutionary history, as the positioning of Schlesneria renders the genus Planctomyces paraphyletic. A re-analysis of published fatty-acid measurements also does not support the current arrangement of the two genera. A quantitative comparison of phylogenetic and phenotypic aspects indicates that the three Planctomyces species with type strains available in public culture collections should be placed in separate genera. Thus the genera Gimesia, Planctopirus and Rubinisphaera are proposed to accommodate P. maris, P. limnophilus and P. brasiliensis, respectively. Pronounced differences between the reported G + C content of Gemmata obscuriglobus, Singulisphaera acidiphila and Zavarzinella formosa and G + C content calculated from their genome sequences call for emendation of their species descriptions. In addition to other features, the range of G + C values reported for the genera within the Planctomycetaceae indicates that the descriptions of the family and the order should be emended.