biology

Sitophilus

Sitophilus 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 Sitophilus rather than just read about it. In short: Sitophilus is a genus of weevils in the tribe Litosomini. Some species are familiar as pests of stored grain, nut, or seed.

Key takeaways

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

Reference excerpt

Sitophilus is a genus of weevils in the tribe Litosomini. Some species are familiar as pests of stored grain, nut, or seed. Notable pest species include the rice weevil (S. oryzae), wheat weevil (S. granarius), and maize weevil (S. zeamais). Among the Stiophilus are species which destroy stored wheat, rice, sorghum, oats, barley, rye, buckwheat, peas, cottonseed, processed cereal products such as pasta, cassava, and fruits such as apples.

Distribution The rice and maize weevils have a nearly cosmopolitan distribution, occurring throughout the warmer parts of the world. In Europe they are replaced by the temperate Palearctic wheat weevil.

Biology The adult female weevil bores a hole in a grain, nut, or seed, and deposits an egg, usually one egg per individual grain. She seals the hole with a secretion. The larva develops while feeding on the interior of the grain, and then pupates. It usually leaves the grain completely hollow when it exits as an adult. The wheat weevil can live on acorns, and may have used them as a host before agriculture made grain plentiful. The rice weevil can live on beans, nuts, grains, and some types of fruit, such as grapes. Several other Sitophilus use the acorns of oaks such as bluejack oak (Quercus incana) and moru oak (Q. floribunda). Some use the seeds of trees in the Dipterocarpaceae and the legume family, Fabaceae. The tamarind weevil (S. linearis) is only known from the seeds of tamarind. Several Sitophilus species are hosts to an intracellular γ-Proteobacterium. Weevil and bacterium have a symbiotic relationship in which the bacterium produces nutrients such as amino acids and vitamins for the host, supplementing its cereal diet.

Diversity As of 1993, there are about 14 species of Sitophilus. Species include:

Sitophilus conicollis Sitophilus cribrosus Sitophilus erosa Sitophilus glandium Sitophilus granarius – wheat weevil, granary weevil Sitophilus linearis – tamarind weevil Sitophilus oryzae – rice weevil Sitophilus quadrinotatus Sitophilus rugicollis Sitophilus rugosus Sitophilus sculpturatus Sitophilus vateriae Sitophilus zeamais – maize weevil Fossil taxa include:

†Sitophilus punctatissimus

References

External links

Obata, H.; et al. (2011). "A new light on the evolution and propagation of prehistoric grain pests: The world's oldest maize weevils found in Jomon Potteries, Japan". PLoS ONE. 6 (3) e14785. Bibcode:2011PLoSO...614785O. doi:10.1371/journal.pone.0014785. PMC 3066187. PMID 21479261.

Illustrations

Worked examples

Example 1 — a first encounter with Sitophilus

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

In research: Sitophilus 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 Sitophilus 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: Sitophilus is common in secondary-school and first-year university syllabi. It links to neighbouring topics Curculionidae genera, Dryophthorinae, Insect pests of millets, so understanding it makes those chapters shorter.
In everyday life: Look for Sitophilus 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 Sitophilus in 20 minutes

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

Frequently asked questions

What is Sitophilus in simple terms?

Sitophilus is a genus of weevils in the tribe Litosomini. Some species are familiar as pests of stored grain, nut, or seed.

Why does Sitophilus 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 Sitophilus?

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 Sitophilus.