Gawrons are strange creatures Samus encounters on planet SR388 during the events of Metroid II: Return of Samus. They have eyes on the tops of their fairly round bodies and what appear to be gaping maws ringed by spines. They fly out of holes in the ground successively (these holes are the entrances to nests housing colonies of the creatures) and attack only by ramming at Samus. Thus, this makes them pretty predictable. They only made their appearance in SR388, and are not seen anywhere else in the series.
Gawrons return in Metroid: Samus Returns, and are encountered in the tunnels of Area 4. They now somewhat resemble green fighter jets, and launch themselves at Samus while respawning infinitely from a fissure in the ground. They can be destroyed easily with a single weapon shot.
"This enemy lives in a nest with many of its kind. When Samus approaches, they will start attacking, one after another."
- It is unknown if the Gawron species was infected by the X Parasites, as Samus never encountered any Gawron-X in Fusion.