The Rolling Maw
This tumbleweed-like plant is actually a carnivorous filter feeder that rolls along the steppe and the desert collecting food as it goes. This particular plant doesn't actually need a water source as it feeds on insects and small animals. It looks much like a dried out scrub, that was uprooted by the wind and damaged through many months rolling on the sands. During the rainy season the Rolling Maw will bloom and spread its seeds to the wind. Once their seeds land in the dry steppe dirt or desert sand, they will germinate and begin growing like many plants. By the end of the rainy season the seedling will be ready to become uprooted and begin their rolling life.
While most normal tumbleweeds are dried out shrubs, the Rolling Maw is still alive and growing. The smallest of these plants feed mostly on insects and microscopic life, but as they grow larger anything that is unfortunate enough to end up in their path is considered a meal. Some of the largest Maws have been known to scoop up the unwary kyrik or elf. If the victim cannot escape the Maw quickly they will be slowly digested much like a pitcher plant.
Rolling Maws are one of the most common hazards for desert crossings. This is especially true during sandstorm season, when you can't see them coming. Caravans will set up camp and use large wooden spikes to prevent any accidental scoopings. Walls in the cities are made more for redirecting Maws than protection from invasion.
Dune Kyriks often tell their children horror stories of about sentient Rolling Maws that hunt down bad children to eat them. But these plants are only as intelligent as your average cactus. They just happen to be mobile, traveling where the wind takes them.