It’s theorized that at one point there was land on the proto-Ghunno but after passing through a large cloud of ice the entire world was flooded.
All life exists below the waters, most relatively deep so as to keep cool. In fact most are either bio-luminescent, use sonar, or both as the depths at which most life exists are rather dark.
Surprisingly there are a small variety of birdlike animals on Ghunno. They live on some of the large bio-luminescent floating plants that circle the planetary ocean. The Ghunno birds mostly use sound echoes to navigate in the air.
An oceanic world, the fourth planet in the Starbright System was heavily bombarded in its history with many different water-bearing comets and asteroids, most of which formed the planetary ocean seen today. Some of said comets contained the building blocks for the oceanic life that formed near the volcanic vents near the ocean floor.