Commonly known as the simple spine lizard, the Haplocanthosaurus was a sauropod dinosaur that was found in the Kimmeridgian stage of the Late Jurassic period which spanned from 155-152 million years ago. There are two known species, Haplocanthosaurus delfsi and Haplocanthosaurus priscus, that belonged to the genus.
Specimens of both the species were discovered by Edwin Delfs, a college student of Colorado, the United States in the lowest layer of the Morrison Formation.
The type species was firstly named Haplocanthus priscus by John Bell Hatcher, an American paleontologist, but since Haplocanthus was already used for acanthodian fish, a new name Haplocanthosaurus priscus was given to the species.
The dinosaur is regarded as one of the smallest sauropods.
The average length of sauropods is estimated to be around over 66 ft (20 m), while the Haplocanthosaurus was around 49 ft (15 m) long and its weight is said to be around 14 tons (12791 kg).
The dinosaur is known for its vertebrae as it possessed a single dorsal neural spine, while a majority of diplodocus sauropods had double-pierced V-shaped dorsal neural spines.
The neck vertebrae had a tall dorsal neural spine, high neural arches, while the thigh bones were quite longer than the shin bones.
Out of the four specimens of these dinosaurs, only the Haplocanthosaurus delfsi is completely mounted, while a partial skeleton is kept in the Cleveland Museum of Natural History with a replica skull as the original skull has not been discovered yet.
Generally, sauropods inhabited freshwater ponds, lakes, rivers, but these dinosaurs must have lived in dense forests, grasslands, rocky mountains. They were gregarious and used to live in groups.
Let's read more fun facts about the Haplocanthosaurus, and if you find this article interesting, don't forget to check out exciting facts about different dinosaurs like Blikanasaurus and Thotobolosaurus.
Haplocanthosaurus Interesting Facts
How do you pronounce 'Haplocanthosaurus'?
The pronunciation of the dinosaur's name seems to be a bit difficult but we are here to make it a little easier for kids. We are going to tell you a simple trick that can be applied to the pronunciation of all the names, be it dinosaurs, animals, places, and many other things.
You just have to break the whole term into several syllables like 'hap-loe-kan-foe-sore-us' to make it less complicated.
What type of dinosaur was a Haplocanthosaurus?
The dinosaur belonged to the class of Reptilia, the clade of Dinosauria and Sauropoda, the family of Haplocanthosauridae, and the Haplocanthosaurus genus. Haplocanthosaurus delfsi and Haplocanthosaurus priscus are two known species of the genus. It is also said that the dinosaur was quite primitive than neosauropods, and macronarians.
In which geological period did Haplocanthosaurus roam the Earth?
The Haplocanthosaurus dinosaur belonged to the Late Jurassic period that spanned from 163-145 million years ago (mya). During this period, the dinosaur must have lived in different parts of the North American continent.
When did the Haplocanthosaurus become extinct?
These sauropods must have become Extinct during the Kimmeridgian stage of the Late Jurassic period, somewhere between 155- 152 million years ago (mya). The reason for extinction is not clear as of now, but dinosaurs became Extinct due to several reasons such as climate change, volcanic eruption, asteroid impact, drought, and many more.
Competition among dinosaurs can also be regarded as one of the major causes of extinction.
Where did Haplocanthosaurus live?
The discovery of the first specimen took place in the lowest layer of the Morrison Formation, Colorado, a US state. Another specimen, known as 'Big Monty' was discovered in Montana. It can be said that the dinosaur must have lived in countries such as the United States, Canada, Mexico, and many more.
What was the Haplocanthosaurus' habitat?
Generally, sauropods inhabited freshwater ponds, lakes, rivers, but these dinosaurs must have lived in dense forests, grassland, rocky mountains. They would have nested in the vicinity of lakes, rivers, and ponds.
Who did Haplocanthosaurus live with?
All species of the Haplocanthosaurus genus lived in groups. We can conclude that they were gregarious by knowing about their communal nesting habits. Young ones formed separate herds, while adults must have taken care of young ones after birth. Also, they must have formed pairs during the breeding season.
How long did a Haplocanthosaurus live?
The exact life span of these primitive dinosaurs is being evaluated by paleontologists. Unlike most Sauropoda species, the species must have lived quite a bit less. Studies of fossils revealed that a few Sauropoda species may have lived for around 100 years.
How did they reproduce?
Like other members of the Dinosauria clade, the primitive dinosaurs reproduced by laying eggs. Their mating patterns were very much similar to modern-day reptiles and birds. Like modern-day animals, these creatures used to perform courtship displays to attract potential partners and it is also scientifically proven that males used to fight over females.
The incubation period was likely to have been between 65-85 days, while the litter size is not known. Recovered fossils suggest that the eggs of sauropods were not bigger than a modern adult goose egg and they weighed less than 11 lb (5 kg) after hatching.
Studies also reveal that the young sauropods were most likely precocial which means they were quite active from their birth.
Haplocanthosaurus Fun Facts
What did Haplocanthosaurus look like?
The Haplocanthosaurus was regarded as one of the smallest sauropods found at the Morisson Formation. The dinosaur was quite shorter and stockier, unlike most dinosaurs of its clade.
It had a short neck and must have eaten plants low to the ground. In other words, we can say the dinosaur was a huge spined lizard. Also, the dinosaur should not be confused with Acrocanthosaurus, a predatory dinosaur that was mainly found in North America.
We've been unable to source an image of Haplocanthosaurus and have used an image of Brontosaurus instead. If you are able to provide us with a royalty-free image of Haplocanthosaurus, we would be happy to credit you. Please contact us at hello@kidadl.com.
How many bones did a Haplocanthosaurus have?
The exact number of bones is not known as of now, but the primitive dinosaur is known for its vertebrae as it possessed a single dorsal neural spine, while a majority of diplodocus sauropods had double-pierced V-shaped dorsal neural spines.
The neck vertebrae had a tall dorsal neural spine, high neural arches, while the thigh bones were quite longer than the shin bones.
The skeleton is kept in the Cleveland Museum of Natural History, though with a replica skull as the original skull has not been discovered yet.
How did they communicate?
Both the species of the Haplocanthosaurus genus communicated in the same way as other dinosaurs. They used to communicate vocally and some researchers believed that they used to roar, but studies state it's not actually true. Like modern-day animals, they must have performed courtship displays during the breeding season to attract potential partners.
How big was the Haplocanthosaurus?
The average length of sauropods is estimated to be around over 66 ft (20 m), while the Haplocanthosaurus was around 49 ft (15 m) long and its weight is said to be around 14 tons (12791 kg). The specimen seemed to be quite a bit bigger than Montanoceratops and Aetonyx.
How fast could a Haplocanthosaurus move?
The thigh bones were substantially longer than the shin bones which suggests it was a very slow-moving dinosaur. However, sauropods had a top speed of around 5 mph (8 kph).
How much did a Haplocanthosaurus weigh?
Sauropods were known for their huge bodies, the average weight of these primitive dinosaurs is said to be around 14 tons (12791 kg).
What were the male and female names of the species?
No specific names have been given to male and female dinosaurs; people generally call them Haplocanthosaurus.
What would you call a baby Haplocanthosaurus?
Like modern reptiles, the babies of these dinosaurs are called hatchlings. Recovered fossils suggest that the eggs of sauropods were not bigger than a modern adult goose egg.
What did they eat?
Generally, sauropods were herbivores and they must have fed on plants and leaves. Since these dinosaurs were small, they must have eaten plants low to the ground, unlike big sauropods. The creature had no sharp teeth and didn't use to bite each other.
How aggressive were they?
The dinosaur was gregarious and often lived in pairs. Dinosaurs, in general, were not aggressive and didn't get violent for no reason. However, while dealing with intruders, they must have turn territorial and aggressive.
Did you know...
Titanosauriformes were the last surviving group of long-necked sauropods.
Why are they called Haplocanthosaurus?
The genus name translates to English as a simple spined lizard as the dinosaur was quite primitive and possessed and an unspecialized spinal cord.
How many specimens of Haplocanthosaurus were found?
As of now, four specimens of these dinosaurs are found. While around seven specimens have been assigned to them, it has not been proved yet whether they belonged to the Haplocanthosaurus genus or not.
Out of the four specimens of these dinosaurs, only the Haplocanthosaurus delfsi is completely mounted, while a partial skeleton is kept in the Cleveland Museum of Natural History with a replica skull as the original skull has not been discovered yet.
Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other creatures from our Amazonsaurus facts, or Argyrosaurus facts for kids.
You can even occupy yourself at home by coloring in one of our free printable Haplocanthosaurus coloring pages.
Main image by FunkMonk (Michael B. H.).
We Want Your Photos!
Do you have a photo you are happy to share that would improve this article?
As a content writer, Abhishek's passion for writing extends beyond professional content creation. With a Bachelor's degree in History from Ram Lal Anand College in Delhi, Abhishek is a skilled writer in both English and Hindi, bringing a creative flair to his work. He enjoys crafting satires and poetry and is dedicated to producing engaging and informative content.
Bachelor of Commerce specializing in Marketing and HR
Pradhanya RaoBachelor of Commerce specializing in Marketing and HR
With a Bachelor’s degree in Commerce from Christ University, Bangalore, Pradhanya's passion for the English language and literature led her to explore the field of content writing, where she has gained extensive experience in writing, reviewing, editing, and fact-checking. She has also earned certifications in Google Ads Search, Google Ads Display, and Social Media Marketing, showcasing her proficiency in digital marketing.
1) Kidadl is independent and to make our service free to you the reader we are supported by advertising. We hope you love our recommendations for products and services! What we suggest is selected independently by the Kidadl team. If you purchase using the Buy Now button we may earn a small commission. This does not influence our choices. Prices are correct and items are available at the time the article was published but we cannot guarantee that on the time of reading. Please note that Kidadl is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon. We also link to other websites, but are not responsible for their content.
2) At Kidadl, we strive to recommend the very best activities and events. We will always aim to give you accurate information at the date of publication - however, information does change, so it’s important you do your own research, double-check and make the decision that is right for your family. We recognise that not all activities and ideas are appropriate for all children and families or in all circumstances. Our recommended activities are based on age but these are a guide. We recommend that these ideas are used as inspiration, that ideas are undertaken with appropriate adult supervision, and that each adult uses their own discretion and knowledge of their children to consider the safety and suitability. Kidadl cannot accept liability for the execution of these ideas, and parental supervision is advised at all times, as safety is paramount. Anyone using the information provided by Kidadl does so at their own risk and we can not accept liability if things go wrong.
3) Because we are an educational resource, we have quotes and facts about a range of historical and modern figures. We do not endorse the actions of or rhetoric of all the people included in these collections, but we think they are important for growing minds to learn about under the guidance of parents or guardians.