biology

Thelypteris

Thelypteris 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 Thelypteris rather than just read about it. In short: Thelypteris (maiden ferns) is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020.

Key takeaways

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

Reference excerpt

Thelypteris (maiden ferns) is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the genus is a very small one with about two species. In other approaches, the genus is the only one in the subfamily Thelypteridoideae, and so includes between 875 and 1083 species. The genus name is from Greek thēlys "female" and pteris "fern". However, "female fern" usually refers to the common lady-fern.

Taxonomy At one time, all thelypterioid ferns were included in the genus Dryopteris because of the sorus shape. However, there are a great many differences between the groups, and these plants are now segregated in their own family. Some researchers include the entire family Thelypteridaceae in the genus Thelypteris. An intermediate position is to place the bulk in Thelypteris (corresponding to Thelypterioideae of PPG I), which can then be divided into subgenera and sections corresponding to the genera of other authors, but to separate out Phegopteris and Macrothelypteris. Another choice is to divide the family into many genera, one of which is Thelypteris. This is the approach taken in the Pteridophyte Phylogeny Group classification of 2016 (PPG I).

Species Using the circumscription of the genus in PPG I, as of May 2023, the Checklist of Ferns and Lycophytes of the World accepted three species:

Thelypteris confluens (Thunb.) C.V.Morton Thelypteris krayanensis K.Iwats. & M.Kato Thelypteris palustris (Salisb.) Schott Other sources place the entire subfamily Thelypteridoideae in the genus, and so accept many more species, including the following (synonyms from the Checklist of Ferns and Lycophytes of the World):

Thelypteris aculeata A.R.Sm. = Amauropelta aculeata Thelypteris appressa A.R.Sm. = Amauropelta appressa Thelypteris bonapartii (Rosenst.) Alston = Amauropelta bonapartii Thelypteris campii A.R.Sm. = Amauropelta campii Thelypteris chimboracensis A.R.Sm. = Amauropelta chimboracensis Thelypteris conformis (Sodiro) A.R.Sm. = Amauropelta conformis Thelypteris correllii A.R.Sm. = Amauropelta correllii Thelypteris dodsonii A.R.Sm. = Amauropelta dodsonii Thelypteris elegantula (Sodiro) Alston = Amauropelta elegantula Thelypteris euthythrix A.R.Sm. = Amauropelta euthythrix Thelypteris fluminalis A.R.Sm. = Amauropelta fluminalis Thelypteris inabonensis Proctor = Amauropelta inabonensis Thelypteris kunthii (Desv.) Morton = Christella normalis Thelypteris macra A.R.Sm. = Amauropelta macra Thelypteris nevadensis (Baker) Clute ex Morton = Parathelypteris nevadensis Thelypteris noveboracensis (L.) Nieuwl. = Parathelypteris noveboracensis Thelypteris ovata R.P.St.John = Pelazoneuron ovatum Thelypteris pilosa (M.Martens & Galeotti) Crawford = Stegnogramma pilosa Thelypteris puberula (Baker) Morton = Christella puberula Thelypteris rosenstockii (C.Chr.) R.M.Tryon = Amauropelta rosenstockii Thelypteris semilunata (Sodiro) A.R.Sm. = Amauropelta semilunata Thelypteris simulata (Davenport) Nieuwl. = Coryphopteris simulata Thelypteris subtilis A.R.Sm. = Amauropelta subtilis Thelypteris verecunda Proctor = Goniopteris verecunda Thelypteris yaucoensis Proctor = Goniopteris yaucoensis

References

Illustrations

Worked examples

Example 1 — a first encounter with Thelypteris

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

In research: Thelypteris 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 Thelypteris 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: Thelypteris is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fern genera, Thelypteridaceae, so understanding it makes those chapters shorter.
In everyday life: Look for Thelypteris 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.

Affiliate

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

How to study Thelypteris in 20 minutes

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

Frequently asked questions

What is Thelypteris in simple terms?

Why does Thelypteris 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 Thelypteris?

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 Thelypteris.