the hard, variously colored, calcareous skeleton secreted by certain marine polyps. 2. such skeletons collectively, forming reefs, islands, etc. 3. the solitary or colonial polyp that secretes this calcareous skeleton.
There are three major known groups of Archaebacteria: methanogens, halophiles, and thermophiles. The methanogens are anaerobic bacteria that produce methane. They are found in sewage treatment plants, bogs, and the intestinal tracts of ruminants.
The Kingdom Archaebacteria consists of bacteria found in harsh environments such as those that are extremely salty or hot. Bacteria in this kingdom have cell walls made without peptidoglycan.It is part of the Domain Archae.ingdom: Archaebacteria Fast FactPhylum: Euryarchaeota Organisms in the genus Picrophilus are currently the most acidophilic organisms currently known.Class: ThermoplasmataOrder: ThermoplasmatalesFamily: PicrophilaceaeGenus: PicrophilusSpecies: oshimae.