In this study, fishes and habitat attributes were quantified, four times over 1 year, on three reefs within four regions encompassing a c. 6° latitudinal gradient across south-western Australia. The variability observed was partitioned at these spatio-temporal scales in relation to reef fish variables and the influence of environmental drivers quantified at local scales, i.e. at the scale of re...

Rhodoliths are unattached calcareous red algae that form extensive beds. Although rhodolith beds are widely distributed in temperate and tropical areas, a recent discovery in the North Pacific Ocean represents a significant northward extension of known rhodolith distribution. This bed, located in Prince William Sound, Alaska, is composed of one rhodolith species, Phymatolithon calcareum, with t...

Patchiness of habitat has important influences on distributions and abundances of organisms. Given the increasing threat of loss and alteration of habitats due to pressures associated with humans, there is a need for ecologists to understand species' requirements for habitat and to predict changes to taxa under various future environmental conditions. This study tested hypotheses about the gene...

Phagotrophy was (and is!) a crucial element in the evolution of photosynthetic eucaryotes. The photosynthetic function in all eucaryotes can be traced to one or more endosymbiotic events involving the ingestion and retention of (unicellular) photosynthetic organisms. In some cases (chloroplasts of green and red algae) this loss of autonomy of the ingested procaryote occurs by transfer of many g...

Womersleyella setacea (Hollenberg) R.E. Norris (Rhodophyta, Ceramiales) is an invasive macrophyte in the Mediterranean Sea, first recorded from the coast of Italy in 1986. This is a review of the geographic distribution and depth limits of W. setacea invasion in the Adriatic Sea since its first record in 1997. Algal turfs were collected and examined from different locations in the Croatian part...

The metabolism of xenobiotics has mainly been investigated in higher plant species. We studied them in various marine macroalgae of the phyla Chlorophyta, Chromophyta, and Rhodophyta. Microsomes contained high oxidative activities for known cytochrome (Cyt) P450 substrates (fatty acids, cinnamic acid, 3- and 4-chlorobiphenyl, 2, 3-dichlorobiphenyl, and isoproturon; up to 54 pkat/mg protein). Th...

Five different RNA extraction methods have been tried out on the red seaweed, Gracilaria changii collected from the mangrove area at Morib, Selangor, Malaysia. Two methods, one utilising guanidinium thiocyanate, and another using cetyltrimethyl ammonium bromide (CTAB), were found to be potential alternatives to obtain pure RNA. By incorporating sand while grinding the tissue, the method using C...

Kappaphycus alvarezii (Rhodophyta, Gigartinales) is a red algae widely cultivated as the main source of raw material for the carrageenan industry. This hydrocolloid is normally used in the food industry as a gelling and stabilizing agent. The facility of its commercial farming based on vegetative propagation promoted the success of the aquaculture of this macroalgae that consequently stimulated...

The effects of increased photosynthetic active radiation (PAR), UV radiation (UVR), and nutrient supply on photosynthetic activity, pigment content, C:N ratio and biomass yield were studied in tank cultivated Gracilaria conferta (Rhodophyta). Electron transport rate (ETR) and biliprotein content were higher under high nutrient supply (HNS), obtained from fishpond effluents, compared to low nutr...

Several species of red algae (Rhodophyta) from the coastal regions of Madagascar have been investigated for their natural products. The most abundant compound was cholesterol (5) in combination with a series of oxidized congeners. The brominated indoles 1-3 along with the sesquiterpene debilone (4) have been isolated from Laurencia complanata. For the first time, debilone (4) has been obtained ...