biology

Petrodactyle

Petrodactyle 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 Petrodactyle rather than just read about it. In short: Petrodactyle (meaning "stone finger") is an extinct genus of ctenochasmatid pterosaur from the Late Jurassic Mörnsheim Formation (Solnhofen limestone) of Bavaria, Germany. The genus contains a single species, P. wellnhoferi, known from a partial skeleton belonging to a subadult individual.

Key takeaways

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

Reference excerpt

Petrodactyle (meaning "stone finger") is an extinct genus of ctenochasmatid pterosaur from the Late Jurassic Mörnsheim Formation (Solnhofen limestone) of Bavaria, Germany. The genus contains a single species, P. wellnhoferi, known from a partial skeleton belonging to a subadult individual. Petrodactyle is one of the largest Solnhofen pterosaurs and one of the largest Jurassic pterosaurs, with an estimated wingspan of 2.1 metres (6.9 ft).

Discovery and naming The holotype and only known specimen, LF 2809, was recovered from the "Dritte Rosa" layer of the Mörnsheim Formation, near Mühlheim in Bavaria, Germany. The specimen was initially discovered in a public visitor's quarry by Günther Zehetner and excavated by quarry owners Roland Pöschl and Uli Leonhard. LF 2809 was acquired by the Lauer Foundation for Paleontology, Science and Education in 2015 and is permanently deposited in their collections. In 2023, Hone et al. described Petrodactyle wellnhoferi as a new genus and species of ctenochasmatid pterosaur based on these fossil remains. The generic name, "Petrodactyle", is derived from the Ancient Greek words petro, meaning "stone", and dactylus, meaning "finger". The name references the name given to Pterodactylus in its initial description in 1809, "Ptero-Dactyle", which was mistakenly printed as "Petro-Dactyle" on the cover. The specific name, "wellnhoferi" honours pterosaur researcher Peter Wellnhofer.

Classification

Hone et al. (2023) assigned Petrodactyle to the clade Ctenochasmatidae as a possible member or relative of the family Gallodactylidae. In their 2024 description of Skiphosoura, Hone et al. scored Petrodactyle into an extensively modified version of the phylogenetic dataset of Pêgas (2024). As was initially speculated by Hone and colleagues in 2023, Petrodactyle was recovered as closely affiliated with gallodactylid taxa such as Normannognathus and Cycnorhamphus. The results of their phylogenetic analysis are displayed in the cladogram below, with derived taxa abbreviated for simplicity.

References

Illustrations

Worked examples

Example 1 — a first encounter with Petrodactyle

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

In research: Petrodactyle 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 Petrodactyle 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: Petrodactyle is common in secondary-school and first-year university syllabi. It links to neighbouring topics Ctenochasmatidae, Fossil taxa described in 2023, Fossils of Germany, so understanding it makes those chapters shorter.
In everyday life: Look for Petrodactyle 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 “Petrodactyle” →

Affiliate

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

How to study Petrodactyle in 20 minutes

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

Frequently asked questions

What is Petrodactyle in simple terms?

Why does Petrodactyle 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 Petrodactyle?

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 Petrodactyle.