Tuscadian pyrosome
The Tuscadian pyrosome was a carnivorous colony species, consisting of thousands of interconnected zooid lifeforms, native to Kokytos. The zooids could assemble themselves into one or more large quadrupedal bodies for attack, which Lieutenant Sylvia Tilly called a "jellyfish from hell". Pyrosomes fed primarily on bioluminescent crustaceans, which they tracked by sensing their electromagnetic signatures; this also caused them to be attracted to active technology with similar signatures. They spent most of their time beneath the ice covering Kokytos, and were highly resistant to phaser fire.

In 3190, a Tuscadian pyrosome attacked the Federation shuttlecraft UFP-11 after it crashed on Kokytos, drawn by the shuttle's power signature. Though the shuttle occupants temporarily diverted it by powering down the shuttle and their equipment, it soon split itself into two bodies and began hunting them across the surface. Tilly was able to distract the creature long enough for the others to contact the  for rescue. ()

Animals