Glow-in-the-dark algae. The species is Pyrocystis lunula. The algae are delivered in a plain plastic bottle.
Bioluminescent algae glow in the dark and emit a blue light when you shake the bottle. They are Dinoflagellates (species name Pyrocystis lunula) and in nature they are found in the North Sea. They are shipped in one or more plain plastic bottles, which may differ slightly from the one in the picture.
Instructions for taking care of the algae: How do I take care of the algae?
More information about bioluminescence: What is Bioluminescence?
Interested in seeing what it looks like? Watch the video below: