Hynerians are an amphibious race of short, frog-like aliens with green skin. They are capable of walking, but their short legs make this difficult. Underwater they move with quick, darting movements with much grace. The one Hynerian seen in the series on a regular basis, Rygel, rides in a hovering "ThroneSled" while out of water. This mode of transportation is probably atypical, however, as Rygel was once a monarch.
When nervous (or angry), Hynerians produce helium flatulence. They possess three stomachs, and spend much of their time eating. If they consume tannot root, their urine and other bodily fluids become explosive. They also have a metabolism that is rapid enough to shrug off some drugs (such as the Nebari mind-cleansing treatment). Hynerians can live in excess of 500 cycles (Rygel himself has lived an unknown number of cycles before becoming a peacekeeper prisoner for a further 130, and when inside Crichton's body mentions that his own has at least 400 more cycles to live).
Hynerian society is split into distinct common and ruling classes and, among the ruling class at least, multiple wives and slaves (often one and the same) are commonplace. Despite this, Hynerian females are not all property. They are quite independent, and even serve as soldiers or spies. The Hynerian Empire is ruled by a monarch called the Dominar, and spans 10,000 planets with a total of 600 billion individuals, though not all of them are of the Hynerian species.
Read more about this topic: List Of Races In Farscape