No abstract

Acyclic and cyclic biphytanes derived from the membrane ether lipids of archaea were found in water column particulate and sedimentary organic matter from several oxic and anoxic marine environments. Compoundspecific isotope analyses of the carbon skeletons suggest that planktonic archaea utilize an isotopically heavy carbon source such as algal carbohydrates and proteins or dissolved bicarbonate. Due to their high preservation potential, these lipids provide a fossil record of planktonic archaea and suggest that they have thrived in marine environments for more than 50 million years.

The mangrove tree crab (Aratus pisonii) is a key member of the arboreal arthropod community of the red mangrove (Rhizophora mangle) swamps of south Florida. Its ecological roles include primary herbivory, predation, and export of biomass and energy in the form of offspring and frass. Although the larval stage is planktonic, distribution of adults and Aratus leaf damage are patchy.

No abstract

The kingdom Crenarchaeota is now known to include archaea which inhabit a wide variety of low-temperature environments. We report here lipid analyses of nonthermophilic crenarchaeotes, which revealed the presence of cyclic and acyclic dibiphytanylglycerol tetraether lipids. Nonthermophilic crenarchaeotes appear to be a major biological source of tetraether lipids in marine planktonic environments.