Wannanosaurus: A Glimpse into the Late Cretaceous Period

Wannanosaurus: A Glimpse into the Late Cretaceous Period

Imagine stepping back in time, about 70 million years ago, to the Late Cretaceous period. As you traverse the lush landscapes of what is now known as Anhui, China, you stumble upon a creature unlike any other. This small yet resilient creature is the Wannanosaurus–a dinosaur that has intrigued paleontologists and dinosaur enthusiasts alike for decades.

The Wannanosaurus, whose name translates to “Wannan Lizard,” is an example of the rich biodiversity that once thrived on our planet. Despite its small size, this dinosaur holds a significant place in the annals of paleontology, offering insights into life during the Late Cretaceous period.

Wannanosaurus Key Facts

KeywordFact
Wannanosaurus pronunciationwa-na-no-sore-us
Meaning of nameWannan Lizard
GroupOrnithopod
Type SpeciesWannanosaurus yansiensis
DietHerbivore
When it Lived70.6 to 66.0 MYA
PeriodLate Cretaceous
EpochEarly/Lower Maastrichtian
Length2.0 ft
Height3.3 ft
Weight0.005 tons
MobilityMoved on two legs
First Discovery1972 by Hou Lian-Hai
Location of first findAnhui, China
First Described byHou Lian-Hai in 1977
HolotypeIVPP V 4447

Wannanosaurus Origins, Taxonomy and Timeline

An artistic rendering of Wannanosaurus, a small dinosaur with a lightweight build. It is depicted with a sleek, brown body and distinctive, elongated spines running along its back, giving it a slightly bristled appearance. The creature stands on two legs with a long tail providing balance.

The name resonates with the location of its discovery–Wannan in China. Behind the name is a fascinating creature from the Late Cretaceous period. The name is derived from ‘Wanna’, the place of its discovery, and ‘sauros’, a Greek word meaning reptile or lizard. 

Belonging to the Ornithopoda group and the Pachycephalosauridae family, the Wannanosaurus is a unique dinosaur. This classification places the Wannanosaurus in a group of dinosaurs known for their bipedal stance and herbivorous diet. Its type species is Wannanosaurus yansiensis. 

This timeline is set in the Late Cretaceous period, specifically the Early/Lower Maastrichtian epoch. This places its existence around a time when the Earth was teeming with diverse life forms and dinosaurs were a dominant presence.

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Discovery & Fossil Evidence

It was first discovered in 1972 by Hou Lian-Hai in Anhui, China. This discovery was a significant milestone in paleontology, shedding light on a previously unknown dinosaur species. The first described specimen, known as the holotype IVPP V 4447, was a partial skeleton that included a partial skull roof, lower jaw, a femur, a tibia, part of a rib, and other fragments. The fused bones in its skull suggest that it was an adult at death.

A photograph showcasing fossilized fragments of Wannanosaurus bones displayed at the Paleozoological Museum of China. The fragments are placed on a textured, beige background, with small identification tags attached to each piece
Jonathan Chen, CC BY-SA 4.0, via Wikimedia Commons

The discovery has provided valuable insights into the diversity of dinosaur species during the Late Cretaceous period. The fossils found have been instrumental in understanding the physical characteristics and lifestyle of this dinosaur. It is known from a single partial skeleton, which includes a partial skull roof and lower jaw, a femur and tibia, part of a rib, and other fragments.

The degree of preservation of the fossils has allowed for a detailed study of its physical characteristics. The flat skull roof with large openings, for instance, has led to it being considered primitive among pachycephalosaurs. This unique feature, along with the other fossil evidence, has contributed significantly to our understanding of this fascinating dinosaur and its relatives.

Wannanosaurus Size and Description

This dinosaur holds a significant place in the realm of paleontology due to its unique position in the family of pachycephalosaurs. Its physical characteristics and the environment in which it thrived provide a fascinating glimpse into life during the Late Cretaceous period.

Short description of Wannanosaurus

It is known for its flat skull roof with large openings, a feature that is considered primitive among pachycephalosaurs. This dinosaur moved on two legs and had an herbivorous diet. Notable specimens have contributed significantly to our understanding of this dinosaur. These specimens, such as the partial skeleton holotype, serve as a testament to the rich biodiversity that once thrived on our planet.

Size and Weight of Type Species

This is one of the smaller dinosaurs–introduced as the second smallest–with an estimated overall length of about 60 cm (2 ft). The femur length of the discovered specimen is approximately 8 centimeters (3.1 in). The size and weight of the Wannanosaurus are indicative of its adaptability and survival instincts.

The Dinosaur in Detail

This herbivorous dinosaur stands out for its distinct features and adaptability. One of its most striking features is its flat skull roof with large openings. This feature is considered primitive among pachycephalosaurs, suggesting that the Wannanosaurus is one of the earlier members of this group.

Its physical characteristics reflect its adaptability and survival instincts. Despite its small size, this dinosaur was able to thrive in a diverse ecosystem and feed on a variety of plant matter and possibly insects. Its bipedal stance allowed it to move swiftly, aiding in its survival.

The partial skeleton discovered includes a femur and tibia that suggest a bipedal stance. The physical characteristics, including its body shape, head, neck, vertebrae, limbs, and tail, provide insights into its lifestyle and survival strategies.

The Wannanosaurus in its Natural Habitat

A digital rendering of Wannanosaurus yansiensis, a small ornithopod dinosaur, set against a gradient green background. The dinosaur is depicted with a grayish body and a red throat, standing on two legs with a long tail balancing its posture.
Cesar Diaz, CC BY-SA 4.0, via Wikimedia Commons

This Chinese dinosaur thrived in the diverse ecosystems of the Late Cretaceous period. The environment during this time was characterized by lush vegetation and a variety of other life forms. With its herbivorous diet, it would have fed on the abundant plant life in its environment.

The bipedal stance suggests that it was a swift mover capable of navigating its environment with ease. This would have been crucial for its survival by allowing it to evade predators and access food sources. Its diet likely consisted of a variety of plant matter and possibly insects, reflecting the biodiversity of its environment.

Despite its small size, this was a resilient creature. Its survival in a diverse ecosystem during the Late Cretaceous period is a testament to its adaptability. Its lifestyle and survival strategies, as inferred from its physical characteristics and fossil evidence, provide fascinating insights into life during this period.

Interesting Points about Wannanosaurus

  1. It is known from a single partial skeleton that includes pieces from multiple parts of the body.
  2. Despite its small size, it was a resilient creature capable of surviving in a diverse ecosystem during the Late Cretaceous period.
  3. The flat skull roof with large openings is considered primitive among pachycephalosaurs, suggesting that it was one of the earlier members of this group. 
  4. It is known to have been herbivorous or omnivorous, feeding close to the ground on a variety of plant matter and possibly insects as well.
  5. It was introduced as the second smallest dinosaur in the world, after the Microceratops. 

Contemporary Dinosaurs

This tiny dinosaur shared its world with a diverse array of contemporaries. Among them were the Psittacosaurus, Shantungosaurus, and Troodon, each occupying different parts of the environment to work with and against the Wannanosaurus.

The Psittacosaurus was a dinosaur considerably larger than the Wannanosaurus that may have been a potential competitor for resources. Yet, with its compact size and agility, the Wannanosaurus might have navigated the dense vegetation of their shared environment with greater ease to access food sources out of reach for its larger contemporary. The Shantungosaurus was a true titan among dinosaurs that towered over the Wannanosaurus. Despite their size difference, these two herbivores likely coexisted peacefully, their diets likely consisting of different plant types–thus reducing competition.

The Troodon, with its keen intellect and sharp claws, presents an interesting contrast to the Wannanosaurus. As a potential predator, the Troodon might have viewed the Wannanosaurus as prey. However, the Wannanosaurus may have been able to use its small size and agility to slip away from this predator. This dynamic interplay between hunter and potential prey adds a layer of complexity to our understanding of the Wannanosaurus’s existence, painting a vivid picture of life in the prehistoric world.

List of All Dinosaurs

We have created a list of all dinosaurs we have covered here, sorted across the seven main groups of dinosaurs. We also include information about their type of diet, (omnivore, herbivore or carnivore) and the time they lived.

Frequently Asked Questions

What does the name mean?

The name translates to “Wannan Lizard,” named after the location in China where it was discovered.

What was its diet?

The Wannanosaurus was primarily an herbivore, feeding on a variety of plant matter and possibly insects.

When was it discovered?

This dinosaur was first discovered in 1972 by Hou Lian-Hai.

Where was it first found?

The first fossil was found in Anhui, China.

Who described it?

It was later described in 1977 by the same person who discovered it, Hou Lian-Hai.

Sources

Please note that the information in this article is based on various sources, drawing on scientific research, fossil evidence, and expert analysis. The aim is to provide a comprehensive and accurate overview of the Wannanosaurus, but please be aware that our understanding of dinosaurs and their world is constantly evolving as new discoveries are made.

This article was last fact checked:Joey Arboleda, 06-13-2023

Featured Image Credit: Jack Mayer Wood, CC BY-SA 4.0, via Wikimedia Commons