biology

Trichomanes

Trichomanes 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 Trichomanes rather than just read about it. In short: Trichomanes is a genus of ferns in the family Hymenophyllaceae, termed bristle ferns. The circumscription of the genus is disputed.

Key takeaways

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

Reference excerpt

Trichomanes is a genus of ferns in the family Hymenophyllaceae, termed bristle ferns. The circumscription of the genus is disputed. All ferns in the genus are filmy ferns, with leaf tissue typically 2 cells thick. This thinness generally necessitates a permanently humid habitat, and makes the fronds somewhat translucent. Because of this membrane-like frond tissue, the plant is prone to drying out. "Filmy ferns" in the taxa Hymenophyllaceae grow in constantly wet environments. Many are found in cloud forests such as "Choco" in Colombia. There are also members of the taxa that can grow submersed in water. The name bristle fern refers to the small bristle that protrudes from the indusia of these ferns.

Taxonomy The genus Trichomanes was first described by Carl Linnaeus in 1753. Its status, like other genera in the subfamily Trichomanoideae, remains disputed. The Pteridophyte Phylogeny Group classification of 2016 (PPG I) accepts the genus as one of eight in the subfamily Trichomanoideae, saying that there are about 60 species. As of October 2019, the Checklist of Ferns and Lycophytes of the World listed about 70 species. Other sources, including Plants of the World Online as of October 2019, treated Trichomanes as the only genus in the subfamily Trichomanoideae, so that it included all the other genera, and had about 250 species.

Phylogeny

Species formerly placed in this genus include:

Trichomanes angustatum Carmich. = Polyphlebium angustatum (Carmich.) Ebihara & Dubuisson Trichomanes bauerianum Endl. = Callistopteris baueriana (Endl.) Copel – Bauer's bristle fern Trichomanes boryanum Kunze 1840 = Cephalomanes atrovirens C.Presl Trichomanes boschianum Sturm ex Bosch = Vandenboschia boschiana (J.W.Sturm ex Bosch) Ebihara & K.Iwats. – Appalachian bristle fern Trichomanes caudatum Brack. = Abrodictyum caudatum (Brack.) Ebihara & K.Iwats. Trichomanes intricatum Farrar = Crepidomanes intricatum (Farrar) Ebihara & Weakley – Weft fern Trichomanes melanopus Baker = Didymoglossum melanopus (Baker) Copel. Trichomanes petersii A.Gray = Didymoglossum petersii (A. Gray) Copel. – Dwarf bristle fern Trichomanes reniforme G.Forst = Hymenophyllum nephrophyllum Ebihara & K. Iwats. Trichomanes speciosum Willd. = Vandenboschia speciosa (Willd.) G. Kunkel Trichomanes tenuissimum Bosch = Polyphlebium tenuissimum (Bosch) comb. ined. Trichomanes venosum R.Br. = Polyphlebium venosum (R.Br.) Copel.

References

Illustrations

Worked examples

Example 1 — a first encounter with Trichomanes

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

In research: Trichomanes 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 Trichomanes 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: Trichomanes is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fern genera, Hymenophyllales, Polypodiidae stubs, so understanding it makes those chapters shorter.
In everyday life: Look for Trichomanes 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 “Trichomanes” →

Affiliate

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

How to study Trichomanes in 20 minutes

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

Frequently asked questions

What is Trichomanes in simple terms?

Trichomanes is a genus of ferns in the family Hymenophyllaceae, termed bristle ferns. The circumscription of the genus is disputed.

Why does Trichomanes 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 Trichomanes?

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 Trichomanes.