biology

Rauisuchus

Rauisuchus 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 Rauisuchus rather than just read about it. In short: Rauisuchus (meaning "Wilhelm Rau's crocodile") is a genus of extinct archosaurs which lived in what is now the Geopark of Paleorrota (Santa María Formation), Brazil, during the Late Triassic period (235–228 million years ago). It contains one species, R. tiradentes.

Key takeaways

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

Reference excerpt

Rauisuchus (meaning "Wilhelm Rau's crocodile") is a genus of extinct archosaurs which lived in what is now the Geopark of Paleorrota (Santa María Formation), Brazil, during the Late Triassic period (235–228 million years ago). It contains one species, R. tiradentes.

Discovery and naming In 1928 or 1929, near the road from Santa Maria to San Jose, Dr. Wilhelm Rau, a German fossil collector working under Friedrich von Huene, discovered the remains of a rauisuchid crocodile. He made the discovery some 20–30 metres (66–98 ft) from the road at a site known as the Zahnsanga, which was likely a ravine or escarpment parallel to the road. The Zahnsanga site was part of the Alemoa Member of the Santa Maria Formation and was found in the uppermost 2.5 metres (8.2 ft) of an 8 metres (26 ft) layer. von Huene then sent the R. tiradentes material back to Germany alongside other fossils, including the holotype of Prestosuchus chiniquensis. von Huene (1936) named Rauisuchus in a list of the Thecodontia, but no diagnosis or description was given, so it remained a nomen dubium until being properly described by von Huene (1942).

Krebs (1973) described the tarsus of R. tiradentes and the lectotype was assigned in 1976 and consists of BSPG AS XXV 60–68, 71–100, 105–119 and 121 (the right premaxilla, right postorbital, left squamosal, left jugal, right pterygoid, right nasal, both splenials, left surangular, prearticular and angular, odontoid(?), axis, cervical, dorsal and caudal vertebrae, ribs, chevron bones, right scapulacoracoid, left pubis, right tibia, fibula and astragalus, and body osteoderms). It is unclear if the lectotype remains belonged to one or two individuals. The specimens found by Rau were eventually re-described by Lautenschlager & Rauhut (2014) and they identified that from Localities 15-17, one or two specimens were found. According to von Huene (1942), 'Find 1025' was assigned to BSPG AS XXV 122 (a partial left maxilla) and 'Find 1020' was assigned to BSPG AS XXV 123 (a cervical vertebra), BSPG AS XXV 124, (a rib fragment), BSPG AS XXV 120 and BSPG, no number (two chevron bone fragments) and BSPG AS XXV 88 (a complete left ilium). Lautenschlager & Rauhut (2014) found that the remains from Locality 15 ('Find 1020') could not be diagnostically assigned to Rauisuchus, and so were removed from the genus. They also noted that von Huene (1942) assigned two more specimens from other localities to R. tiradentes: several isolated teeth, BSPG AS XXV 101 (the proximal end of an ulna) and BSPG AS XXV 102 (a partial metatarsal), but these cannot be confidently assigned to R. tiradentes as no overlapping material is known.

Description Rauisuchus is distinguished from other members of the Rauisuchidae on the basis of a knob-like thickening on the base of the posterior process of the premaxilla, short, ventrally keeled cervicals, lacking postzygodiapophyseal laminae, and elongated caudals with an accessory neural spine and a postspinal lamina.

Classification Rauisuchus belonged to a group of land-dwelling relatives to crocodiles known as the Rauisuchidae, although it was initially assigned to the Theriodontia in 1936. Rauisuchids were among the top predators of their day, eating other reptiles for food and maybe hunting early dinosaurs. It was placed as the sister taxon to Tikisuchus and Yarasuchus, forming a clade with the two.

References

Illustrations

Worked examples

Example 1 — a first encounter with Rauisuchus

Start with the simplest possible case. Write down what Rauisuchus 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 Rauisuchus 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 Rauisuchus 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 Rauisuchus

In research: Rauisuchus 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 Rauisuchus 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: Rauisuchus is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fossil taxa described in 1936, Fossils of Brazil, Prehistoric pseudosuchian genera, so understanding it makes those chapters shorter.
In everyday life: Look for Rauisuchus 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.

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How to study Rauisuchus in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Rauisuchus 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 Rauisuchus out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Rauisuchus in simple terms?

Why does Rauisuchus 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 Rauisuchus?

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 Rauisuchus.