biology

Mexican blind brotula

Mexican blind brotula 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 Mexican blind brotula rather than just read about it. In short: The Mexican blind brotula (Typhlias pearsei) is a species of viviparous brotula, of the family Dinematichthyidae, endemic to Mexico, where it is found in sinkholes and caves. It is known as sak kay in Mayan and dama blanca ciega in Spanish.

Key takeaways

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

Reference excerpt

The Mexican blind brotula (Typhlias pearsei) is a species of viviparous brotula, of the family Dinematichthyidae, endemic to Mexico, where it is found in sinkholes and caves. It is known as sak kay in Mayan and dama blanca ciega in Spanish. This cavefish grows to a standard length of 9.7 cm (3.8 in). It is the only known member of its genus.

Description The Mexican blind brotula has a large, laterally compressed, scaleless head with no eyes, but several papillae and cavities which contain sensory organs. The nostrils are located on the upper lip and the mouth has a longitudinal split at the back. The body bears scales and has long dorsal and anal fins which terminate close to, but are separate from, the caudal fin. The dorsal fin has no spines and 75 to 87 soft rays, and the anal fin has no spines and 59 to 68 soft rays. The male has two pairs of pseudoclaspers, the inner ones being in front of the outer ones. The standard length is about 9.7 cm (3.8 in). The skin does not contain pigment, making the fish appear pinkish-white.

Distribution The Mexican blind brotula inhabits the cenotes (water-filled sink holes connected through subterranean rivers) and aquifers in the Yucatán Peninsula of Mexico, where the temperature is between 23 and 27 °C (73 and 81 °F) throughout the year. These are typically anchialine (connected to the sea), but the Mexican blind brotula is only known from the sections with fresh or brackish water.

Ecology

The Mexican blind brotula is the top predator in the Yucatán aquifer system and is probably not very numerous. It feeds on crustaceans such as shrimps and mysids that also inhabit the aquifers. In some locations, it is associated with another blind fish, the blind swamp eel (Ophisternon infernale) and in one cave system, with the catfish Rhamdia guatemalensis. It does not react to light, but is very sensitive to vibrations. It is a viviparous fish, giving birth to up to a dozen young between December and February. The newborns are yellowish and about 2.4 to 3.7 cm (0.9 to 1.5 in) in length.

Status The main threat faced by this fish is from water pollution; the aquifers in which it lives are below inhabited areas with inadequate sanitary arrangements, so that coliform bacteria may leak in, and excess nitrates may be in wastewater. The International Union for Conservation of Nature has rated the conservation status of this fish as being "near threatened".

Etymology The generic name derives from the Greek typhlos meaning "blind" and the specific name honours the American ecologist, Arthur Sperry Pearse (1877-1956), who was the collector of the type specimen used by Carl Leavitt Hubbs to describe the species. The generic synonym "Typhliasina" was declared as an unneeded replacement name in 2017.

References

External links Media related to Typhliasina pearsei at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with Mexican blind brotula

Start with the simplest possible case. Write down what Mexican blind brotula 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 Mexican blind brotula 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 Mexican blind brotula 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 Mexican blind brotula

In research: Mexican blind brotula 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 Mexican blind brotula 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: Mexican blind brotula is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bythitidae, Cave fish, Endemic fish of Mexico, so understanding it makes those chapters shorter.
In everyday life: Look for Mexican blind brotula 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 “Mexican blind brotula” →

Affiliate

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

How to study Mexican blind brotula in 20 minutes

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

Frequently asked questions

What is Mexican blind brotula in simple terms?

Why does Mexican blind brotula 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 Mexican blind brotula?

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 Mexican blind brotula.