Asilisaurus kongwe is a dinosauromorph — an animal extremely close to dinosaurs, but not technically a true dinosaur. The name breaks down as follows:
Asilisaurus: “Asil lizard,” named after the Asil region of Tanzania
Kongwe: Swahili for “ancient”
Together, the name means “ancient Asil lizard.”
It lived in what is now Tanzania during the Middle Triassic, a time when the dominant land predators were rauisuchians, the true rulers of that ecosystem. Asilisaurus was relatively small, measuring 7–10 feet (2–3 meters) long, about 3 feet tall at the hip, and weighing roughly 20–30 kg (45–65 lbs). The species was formally described in 2010.
What Made Asilisaurus Unique?
Asilisaurus was not quite a dinosaur — it was a dinosauromorph, meaning it lived right before true dinosaurs appeared and represents a close evolutionary relative.
Evolutionary Chain
Reptiles
↓
Archosaurs (crocodiles + dinosaurs)
↓
Dinosauromorphs
↓
Asilisaurus (near-dinosaur cousin)
↓
True Dinosaurs
This position makes Asilisaurus one of the clearest examples of how dinosaurs evolved. It belonged to a group called silesaurids, animals that sit immediately beside dinosaurs on the evolutionary tree.
Anatomy
Hind Limbs
The hind limbs of Asilisaurus are especially important. Its femur angled inward toward the body, creating a pillar-like leg posture rather than a sprawled reptile stance. This adaptation provided:
Greater energy efficiency
Reduced fatigue during long movement
Faster sustained locomotion
Improved balance while navigating uneven terrain
These traits foreshadow the upright walking style of dinosaurs.
Feet
Its feet were built for efficient movement:
Three main weight-bearing toes
A reduced fourth toe positioned too high and short to function in locomotion
This foot design later became the standard in many dinosaurs, particularly theropods.
Tail
The tail vertebrae were lightly built and partially hollow, reducing weight without sacrificing strength. The tail was long and had a strong muscular base, acting as a counterbalance that helped maintain stability and control during movement.
Diet
Asilisaurus was a bulk browser, feeding on low- to mid-height vegetation common in the Triassic period, including:
Fern mats
Seed ferns
Cycads
Early conifers
Horsetail plants
Soft shoots
As a herbivore, it likely spent much of its day feeding to meet its energy needs.
Brain and Intelligence
Its brain was relatively small compared to its body, similar to modern reptiles. However, this does not imply poor intelligence. Reptiles are highly capable animals, and Asilisaurus likely possessed the awareness and coordination needed to survive in predator-rich environments.
Conclusion
Asilisaurus was not a true dinosaur, but it represents a prototype of dinosaur evolution — a crucial step in understanding how dinosaurs developed their signature posture, movement, and lifestyles.
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