The "Darmats" (an abbreviation of "dark matter") are a sapient race of beings made out of a form of dark matter. They live in the open space surrounding the galaxies and have existed since the beginning of the Universe itself.
The Darmats are spherical creatures, each roughly the size of Jupiter, which communicate by radio waves for short distances and hyperspace radio for long distances. The atoms that make up their bodies are made of two previously unknown flavors of quarks which form structures roughly analogous to protons and neutrons, but with no electrical charge whatsoever, so that the only way they interact with electromagnetism of any kind is through the space dust particles made up of baryonic matter that stick to their bodies. Besides that, they don't interact with baryonic matter at all, except through gravity.
They are mostly peaceful creatures which joyfully shape up entire galaxies as works of art. They reproduce by binary fission.