40 research outputs found
Estimates of nuclear DNA content in 98 species of brown algae (Phaeophyta)
Despite the fact that brown algae are critical components of marine ecosystems around the world only one species has had its genome sequenced. To facilitate genome studies in the class we report data for 12 of the 19 recognized orders
Taxonomy of the Dictyota ciliolata-crenulata complex (Dictyotales, Phaeophyceae)
We reassessed the taxonomy of dentate Dictyota species formerly attributed to D. ciliolata and D. crenulata. Both taxa have long been assumed to be broadly distributed in tropical to warm-temperate seas. Recent molecular data, however, provided evidence that D. crenulata constituted a complex of at least four species with restricted geographical distributions. Based on those results and careful morphological examination, we split D. crenulata sensu lato into D. crenulata sensu stricto restricted to Pacific Central America, D. jamaicensis with a tropical amphi-Atlantic distribution and D. canariensis and D. pleiacantha sp. nov. from Macaronesia. Morphological analysis showed that these species were distinguished by subtle morphological differences. In contrast to D. crenulata sensu lato, the wide tropical distribution of D. ciliolata was confirmed by DNA data. In addition, psbA sequence analysis did not provide evidence to segregate D. menstrualis and D. plectens from D. ciliolata
Methods to study organogenesis in decapod crustacean larvae II: analysing cells and tissues
Cells and tissues form the bewildering diversity of crustacean larval organ systems which are necessary for these organisms to autonomously survive in the plankton. For the developmental biologist, decapod crustaceans provide the fascinating opportunity to analyse how the adult organism unfolds from organ Anlagen compressed into a miniature larva in the sub-millimetre range. This publication is the second part of our survey of methods to study organogenesis in decapod crustacean larvae. In a companion paper, we have already described the techniques for culturing larvae in the laboratory and dissecting and chemically fixing their tissues for histological analyses. Here, we review various classical and more modern imaging techniques suitable for analyses of eidonomy, anatomy, and morphogenetic changes within decapod larval development, and protocols including many tips and tricks for successful research are provided. The methods cover reflected-light-based methods, autofluorescence-based imaging, scanning electron microscopy, usage of specific fluorescence markers, classical histology (paraffin, semithin and ultrathin sectioning combined with light and electron microscopy), X-ray microscopy (µCT), immunohistochemistry and usage of in vivo markers. For each method, we report our personal experience and give estimations of the method’s research possibilities, the effort needed, costs and provide an outlook for future directions of research