Achivars are a non-sapient species of quadrupedal herbivores native to the planet Tran-ky-ky.
Described by Skua September as "ice-skating porcupines", Achivars are furry pig-sized quadrupeds which move over the frozen ice oceans of Tran-ky-ky in large groups, foraging for vegetation. Interspersed with their fur are numerous meter-long mobile quills with wing-like membranes at the tip which act as wind sails. Their broad, flat feet function as pads to skate over the ice smoothly, propelled by the omnipresent wind. Despite serving primarily for locomotion, the Achivars' spines are as sharp as an Earth porcupine's and therefore useful for defense as well. Their eyes are large and bright-red. Their heads are proportionally small and joined directly to their bodies without visible necks. They're preyed upon by the serpentine Dyella.
- The Deluge Drivers, by Alan Dean Foster (1987)