Mangalix
The Mangalix has specialized to “breathe” manganese compounds in the silt or nearby ocean water. Their numbers are low in most places, making concentrations of them impossible to see with the naked eye.
However, when a Geletaventria organism dies (such as from disease or injury between others of its kind), Mangalixes’ numbers surge on the corpse. The bounty of manganese compounds in the corpse’s body tissue or stomach contents allows them to run at high metabolic rates and reproduce rapidly. Mangalixes can live on more complicated hydrogen-based compounds than their ancestor, and can even rip apart the Geletaventrian’s hemerythrin-based blood to use the hydrogen it contains.
Mangalixes so gorge on violet blood that their entire bodies may be tinted violet, much like a mosquito's abdomen turning red from its blood meals. In sufficient numbers, Mangalixes coat the insides of a dead organism with a light periwinkle-colored biofilm. The insides of a dead Devoratorian can be surprisingly colorful, with red Melter Detritis feasting on its chitinous internal structures, various colors of Glow Detritis living on more exposed tissues, and shades of Mangalix (violet, periwinkle, slightly bluish white) on blood and blood-filled tissues.
Infection
Occasionally Mangalixes end up in the exposed wounds of Devoratorians when the silt is disturbed or when the Devoratorian gets in contact with silt. Short of any anti-pathogen/parasite defenses in the blood, the Mangalix multiplies out of control, using all the manganese it can and causing the death of the host.
Relationships
In LadyM Twilight Slope and LadyM Twilight Floor, it sometimes competes with the Grox, which also “breathes” manganese. The two are not in direct competition for food, as (outside corpses) one eats hydrogen compounds and another eats detritus. However, the Grox hoards manganese crystals within its body as its own personal “air supply”, and where useful manganese compounds are scarce, it has a big effect on Mangalixes. The Grox also eats decaying blood and blood-filled body tissue, although only when well-decayed into detritus.
Mangalixes also have an antagonistic relationship with Glow Detritis. Glow Detritis are also scavenging microbes with no need for oxygen, so they compete for the same resources. In sufficient numbers, the Glow Detritis create a visible glow. If they cover exposed areas of the carcass, the Glow Detritis’ glow attracts scavengers which feast on the corpse. While Glow Detritis can survive a trip through the fauna’s digestive system, Mangalixes cannot. Unless the scavenging fauna has open wounds in or around its mouth, the Glow Detritis doom any Mangalixes that are inadvertently eaten with them. Despite this antagonistic relationship, many Mangalixes at a decaying carcass survive, due to pooling into the silt around the body.
Like its ancestor, it cannot digest copper: in fact, it's poisonous to it. It is also weak to high levels of concentrations of chlorine compounds, as many Earth microbes are.