Plasmidines are a silicon-based lifeform made of plasma.
The origins of plasmidines are a high topic of debate. Plasmidine fossils are extremely rare and it is extremely difficult to use absolute dating on plasmidine fossils due to the short half-life of silicon isotopes.
Absolute dating has been tested on novarium but this also didn't offer many results. There is very little research on novarium since it is a rare mineral exclusive to plasmidine biology. There isn't enough fossils to research and it's too dangerous to operate on living plasmidines.
Unable to use absolute dating as a reliable method, researchers rely on relative dating and historical records for piecing together plasmidine evolutionary history.
The anatomy of plasmidines is deceptively simple. While they have very few organs and only one biological sex, each organ performs multiple complicated functions. These organs and functions are not totally understood.
The membrane is a thick, relatively soft, and impermeable container for the plasma and metal piece. The insides of a plasmidine often gets very hot so the membrane also acts as an insulator to protect both the plasma and the plasmidine's environment.
The membrane is made up of several layers. Some areas, such as the corona, have fewer layers and are thus are thinner and more permeable.
Electrically conductive gasses that flow through the body. The plasma acts similarly to blood and organs in organic animals.
Excess, non-conductive gasses stored elsewhere on the body. It is protected by a thinner, more permeable, and broken layer of membrane.
The novarium metal piece helps conduct plasma around the body similar to how a human heart pumps blood. It is usually found somewhere in the center of the body since plasma flows around it. The metal piece is solid due to high pressure and the extremely high melting point of novarium.
Plasmidines are able to change their form over a stretch of time because of the metal piece. Plasmidines will often change their form in order to socially adapt to other species.
As certain gasses decay into minerals, those minerals deposit into lower-circulation areas of the body. The most reliable method for finding the age of a living plasmidine is to look at how much mineral has settled.
As plasmidines have no known origin, there is historically very little evidence of centralized, solely plasmidine societies. Instead, they often assimilate into other species societies. They will change their forms in order to match the outward appearance of other species as closely as possible.
Plasmidines have varying amounts of sentience based on what species they adapt to. Some of the most common forms of plasmidines are taken after species that reached galactic expansion or spacefaring, but there are plasmidines who take the form and level of sentience as feral animals.