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Genetic memory, sonar communication and projections, males- prominent feature
|Out of universe information|
- "Ah, but not actually a whale. Whale-like, but not a mammal. It’s a fish. It’s a big, big fish"
- — Rodney McKay
A Flagisallus is a large fish creature that lives in the oceans on Lantea.
- "I cross-referenced the renderings in the database with the whale outside and, you’ll see... The males have a rather prominent..."
- — Rodney McKay
The Flagisallus are similar in appearance to, and is often confused with, Earth Whales, Flagisallus are actually fish while whales are mammals. Flagisallus are quite intelligent and possess a form of sonar language, coupled with an EM field which they can also use to communicate with each other and with other beings such as Ancients and Humans through the use of auditory and visual projections. The Flagisallus can live in depth below 350 meters below the surface. Male Flagisallus have a prominent features that distinguishes them from females. (ATL: "Grace Under Pressure", "Echoes")
Before the Lanteans left for Earth they had already built a device which would record the sonar communications from the Flagisallus and teach them their own language in return. During this time the star in the system underwent a Coronal mass ejection and most of the crew of the Adaris which raced back to Lantea to warn Atlantis, who raised the shield and encompassed a significant portion of the planet. This event was coded into the Flagisallus' genetic memory. (ATL: "Echoes")
In 2005 Dr. Rodney McKay was trapped in the back of a sinking Puddle Jumper and activated the emergency beacon which attracted one of the Flagisallus, later called Sam by Dr. McKay. A year later, another Coronal mass ejection was occuring and so the Flagisallu began to flock to Atlantis to be protected by its shield. Their sonic projections began to cause internal pressure with the Atlantis expedition members brains and some began to die. (ATL: "Grace Under Pressure", "Echoes")