biology

Wuerhosaurus

Wuerhosaurus is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Wuerhosaurus rather than just read about it. In short: Wuerhosaurus is an extinct genus of stegosaurine stegosaur dinosaurs from the Early Cretaceous of China. The genus contains two species, Wuerhosaurus homheni, the type species named in 1973, and Wuerhosaurus ordosensis, named in 1993.

Key takeaways

Wuerhosaurus belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Wuerhosaurus to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Wuerhosaurus from memory before moving on to harder problems.

Reference excerpt

Wuerhosaurus is an extinct genus of stegosaurine stegosaur dinosaurs from the Early Cretaceous of China. The genus contains two species, Wuerhosaurus homheni, the type species named in 1973, and Wuerhosaurus ordosensis, named in 1993. It is one of the youngest (most recent) known stegosaurs in the fossil record, alongside Mongolostegus and Yanbeilong.

Discovery and species

Wuerhosaurus homheni is the type species, described by Dong Zhiming in 1973 from the Tugulu Group in Xinjiang, western China. The generic name is derived from the city of Wuerho. Three separate localities in the Wuerho Valley were discovered to contain material from the new stegosaur: 64043-5, 64043 and 64045. The remains consisted of the holotype, Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) V.4006, a skull-less fragmentary skeleton, and the paratype IVPP V.4007. Holotype material includes a mostly complete pelvis and sacrum lacking the ischium, the first caudal vertebrae, two dorsal vertebrae, a scapulocoracoid, humerus and phalanx, as well as two dermal plates. Three posterior caudal vertebrae from the tail and a partial ulna of a second individual form the paratype, and Dong referred a partial ischium from a third locality to Wuerhosaurus. A smaller stegosaur from the Ejinhoro Formation in the Ordos Basin in Inner Mongolia was found in 1988. When the specimen (IVPP V.6877) was described by Dong in 1993, it was named W. ordosensis, as it was from a similar age and had a similar anatomy. The holotype of the species includes a nearly complete torso, consisting of three cervical vertebrae, all eleven dorsal vertebrae (with attached ribs), a complete sacrum with a right ilium, and the first five caudal vertebrae, all articulated. An additional dorsal vertebra and dermal plate were referred to the taxon when it was named. In 2014 Roman Ulansky named a new species of Wuerhosaurus, "W. mongoliensis" for vertebrae and pelvic material, but the name is an invalid nomen nudum. It was formally described as Mongolostegus in 2018.

Description Wuerhosaurus homheni was probably a broad-bodied animal, reaching 7 metres (23 ft) in length and 4 metric tons (4.4 short tons) in body mass. Only a few scattered bones have been found, making a full restoration difficult. Its dorsal plates were at first thought to have been much rounder or flatter than other stegosaurids, but Maidment established this was an illusion caused by breakage: their actual form is unknown. W. homheni had a pelvis of which the front of the ilia strongly flared outwards indicating a very broad belly. The neural spines on the tail base were exceptionally tall. In contrast, W. ordosensis was much smaller, estimated by Paul to have been 5 m (16 ft) long and weigh 1.2 metric tons (1.3 short tons). It had a relatively long neck with a broad pelvis, but the neural spines are shorter.

Classification

Phylogeny Wuerhosaurus is one of the most derived stegosaurians, being closely related to either Dacentrurus and Hesperosaurus, or Hesperosaurus and Stegosaurus, depending on phylogenetic analysis. Carpenter et al. (2001) recovered Wuerhosaurus in the former relationship, close to Hesperosaurus and Dacentrurus as basal in Stegosauridae. Wuerhosaurus was recovered in a different position by Escaso et al. (2007), still related to Hesperosaurus, but basal to a clade of Lexovisaurus and Stegosaurus. Maidment et al. (2008) recovered a different placement with Wuerhosaurus as being in a clade of taxa in derived Stegosaurinae, most closely related to Hesperosaurus and then Stegosaurus. More recently, Maidment (2017) elaborated upon her earlier analyses, and instead resolved Wuerhosaurus as closest to Stegosaurus, with Hesperosaurus being more closely related to Miragaia. These results are shown below.

Synonymy with Stegosaurus Maidment and colleagues proposed in 2008 that Wuerhosaurus was a junior synonym of Stegosaurus, with W. homheni being renamed Stegosaurus homheni, and W. ordosensis being a dubious taxon. W. homheni was synonymized because the holotype that could be located was similar to Stegosaurus, and because of its phylogenetic position. Wuerhosaurus placed between Stegosaurus and Hesperosaurus, the latter being considered a species of Stegosaurus because of its age, location, and anatomy. Since Wuerhosaurus placed between two possible Stegosaurus species, Maidment et al. synonymized the taxon as well. Wuerhosaurus ordosensis was considered to be a nomen dubium because the holotype could not be found in the IVPP collections. The original description did not mention any valid diagnostic traits, and no other description provided features either, so Maidment et al. considered the taxon undiagnostic. This opinion has been contested, however, by Carpenter (2010). He discussed how the diagnoses and features used by Maidment et al. were inconsistent and generalized, with Wuerhosaurus homheni bearing numerous differences. As such, Carpenter advocated for the separation of both Hesperosaurus and Wuerhosaurus from Stegosaurus. In 2017, Hou and Ji described and isolated stegosaur sacrum with paired ilia that they referred to W. ordosensis based on similarities to the holotype. The researchers concluded that several anatomical features separated this species from W. homheni.

Paleoecology The type species, W. homheni, is known from the Tugulu Group, while W. ordosensis is known from the Ejinhoro and Luohandong Formations. The approximate age of Wuerhosaurus is 130 mya, based on the approximate dating of the Tsaganstabian fauna, and thus the stegosaur would have lived in the Hauterivian era, which is roughly coeval with the Wealden group, from which other stegosaur material has been found. Uranium-lead dating has shown that the age of Wuerhosaurus in the Lianmuqin Formation of the Tugulu Group is slightly younger than 135.2 million years old, while Wuerhosaurus in the Ejinhoro Formation is from the Barremian. Stegosaur footprints from the Tugulu Group in Xinjiang Province, China, have been attributed as registered by W. homheni individuals. These tracks include the world's smallest stegosaur tracks, measuring 5.7 cm in length, indicative of a dinosaur that was approximately cat-sized.

Illustrations

Worked examples

Example 1 — a first encounter with Wuerhosaurus

Start with the simplest possible case. Write down what Wuerhosaurus claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Wuerhosaurus before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Wuerhosaurus ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Wuerhosaurus

In research: Wuerhosaurus appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Wuerhosaurus in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Wuerhosaurus is common in secondary-school and first-year university syllabi. It links to neighbouring topics Barremian dinosaurs, Dinosaur genera, Dinosaurs of China, so understanding it makes those chapters shorter.
In everyday life: Look for Wuerhosaurus outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Wuerhosaurus” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Wuerhosaurus in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Wuerhosaurus means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Wuerhosaurus out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Wuerhosaurus in simple terms?

Why does Wuerhosaurus matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Wuerhosaurus?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Wuerhosaurus.