Fangyanosaurus

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***Fangyanosaurus*** ("Lizard of Fangyan") is a genus of tyrannosauroid dinosaur hailing from the Late Cretaceous Fangyan Formation of Zhejiang Province, China. At 10 feet long, *Fangyanosaurus* would have been a relatively small hunter. It probably used its slender legs to chase after prey, as well as escape from predators like *Yiwusaurus*.

The type species of *Fangyanosaurus*, ***F. cretanatus***, differed from contemporary tyrannosauroids in that it had a small subnarial gap between the premaxilla and maxilla, though not as noticeable as that of *Dilophosaurus*. It is generally thought that this unusual feature made it more effective in tearing away at flesh.

## Description

*F. cretanatus* is a modest-sized theropod that had a few features that were not seen in similar tyrannosauroids.

### Size

In the past, there has been some debate as to what size *Fangyanosaurus* was. The original description by Huan Ji Qing stated that the animal reached lengths of 16 feet (5 m). A study in 2007 by paleontologists at the University of Washington seemed to point towards *Fangyanosaurus* being a very large tyrannosauroid, potentially weighing up to 1.5 tonnes (1.6 short tons) and reaching 23 feet (7 m) long. However, many paleontologists scorned this study because of its incompetent usage of measurements, including mixing up the length of the skull of *Fangyanosaurus* with that of the somewhat similar *Alioramus*. More recently, a 2017 study by students at Harvard University decided on a much smaller size for *Fangyanosaurus*, specifically a total length of 10 feet (3.3 m) and a weight of 200 lbs. (90 kg.) for a large adult. That estimate was revised slightly in 2019 when more material was found. Nowadays, it's generally accepted that *Fangyanosaurus* was around 10 feet (3.3 m) long, and weighed approximately 180 lbs. (80 kg) at adulthood.

### Skull

The skull of *Fangyanosaurus* had a subnarial gap like that of *Dilophosaurus*. Because it was not quite as large as that of *Dilophosaurus*, it served a different purpose. Some scientists say the notch had powerful muscles attached, allowing for bone-crushing bites. However, a study done by researchers at the Edmonton Institute for Paleontology (EIP) in 2014 found that the subnarial notch was not the correct shape to anchor muscles. Instead, it suggested the notch may have been used as a means of tearing meat. This was supported in 2015 due to a detailed description of the holotype skull of *Fangyanosaurus*. The scientists involved found that the teeth on the subnarial notch, as well as the entire maxilla, were robust and well adapted to resist the stress of tearing at prey. This suggested that *Fangyanosaurus* likely relied on gripping and tearing rather than powerful bites to deal with prey.

The mandibular fenestra was very small, suggesting a weaker bite than that of other tyrannosauroids. In comparison, the orbital, antiorbital, and temporal fenestrae were all quite large, pointing at a lightweight skull. Unusually, there were stiffened rods of cartilage along the lips. This might have helped with making the skull much more robust than most other small tyrannosauroids.