Philodina erythrophthalma
Philodina erythrophthalma is also a rotifer that feeds on bacteria that swim and
crawl. Its body length is 300–500 μm; they generate a strong current using the ciliary
ring at the anterior end, eat bacteria, and multiply. When population sizes increase
parthenogenically (a female develops from a diploid summer egg), and biotope
conditions worsen, males develop from the haploid egg, which are produced by a
reduction in division that typically forms winter eggs (pause eggs). The walls of
winter eggs are dryer and thicker than those of summer eggs when resistant to
fertilization. As biotope conditions improve, a female then develops from a winter
egg. The limbs adjust such that there are two of them at the posterior end, and there
are four hocks.
Aeolosoma hemprichi
Aeolosoma hemprichi is a detritivorous oligochaete (i.e., an aquatic earthworm). Its
body length ranges from 500 to 1000 μm, and it appears in natural ecosystems, such
as lakes and marshes, and in artificial ecosystems, such as the wastewater treatment
systems of activated sludge and in biofilms. It exhibits a subcutaneous, crimson
grease spot and has bunched bristles on each metamere for both of its two pairs of
stomachs. This species eats bacteria and other microbes, such as protists and
flocculated cells, multiplies by cell division, and excretes fecal pellets.
3.3.3 Bacterial Decomposers
Bacillus cereus
Bacillus cereus is a large, gram-positive aerobic bacterium in the Bacillus genus that
has spores. It is abundant in the natural world, including in soils and polluted waters,
and its growth is poor under acidic conditions. It causes food poisoning, and, as an
3 Maintenance of the Microcosm N-System
25
Philodina erythrophthalma is also a rotifer that feeds on bacteria that swim and
crawl. Its body length is 300–500 μm; they generate a strong current using the ciliary
ring at the anterior end, eat bacteria, and multiply. When population sizes increase
parthenogenically (a female develops from a diploid summer egg), and biotope
conditions worsen, males develop from the haploid egg, which are produced by a
reduction in division that typically forms winter eggs (pause eggs). The walls of
winter eggs are dryer and thicker than those of summer eggs when resistant to
fertilization. As biotope conditions improve, a female then develops from a winter
egg. The limbs adjust such that there are two of them at the posterior end, and there
are four hocks.
Aeolosoma hemprichi
Aeolosoma hemprichi is a detritivorous oligochaete (i.e., an aquatic earthworm). Its
body length ranges from 500 to 1000 μm, and it appears in natural ecosystems, such
as lakes and marshes, and in artificial ecosystems, such as the wastewater treatment
systems of activated sludge and in biofilms. It exhibits a subcutaneous, crimson
grease spot and has bunched bristles on each metamere for both of its two pairs of
stomachs. This species eats bacteria and other microbes, such as protists and
flocculated cells, multiplies by cell division, and excretes fecal pellets.
3.3.3 Bacterial Decomposers
Bacillus cereus
Bacillus cereus is a large, gram-positive aerobic bacterium in the Bacillus genus that
has spores. It is abundant in the natural world, including in soils and polluted waters,
and its growth is poor under acidic conditions. It causes food poisoning, and, as an
3 Maintenance of the Microcosm N-System
25