science

Hadronyche formidabilis

Hadronyche formidabilis is a science 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 Hadronyche formidabilis rather than just read about it. In short: Hadronyche formidabilis, the northern tree-dwelling funnel-web spider, is a medically significant mygalomorph spider found in Queensland and New South Wales. It is also known as the Northern Rivers funnel-web spider or northern funnel-web spider.

Key takeaways

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

Reference excerpt

Hadronyche formidabilis, the northern tree-dwelling funnel-web spider, is a medically significant mygalomorph spider found in Queensland and New South Wales. It is also known as the Northern Rivers funnel-web spider or northern funnel-web spider.

Taxonomy A member of the genus Hadronyche, the northern tree-dwelling funnel-web spider was first described in 1914, by William Joseph Rainbow in the genus Atrax, having been collected from the vicinity of the Richmond River. Rainbow suspected it may have needed to be placed in a genus separate to Atrax at the time, but demurred due to the lack of male specimens. The species name is derived from the Latin formidabilis "terrifying". Within the genus Hadronyche, it is classified in the heterogeneous cerberea group, alongside the southern tree-dwelling funnel-web (H. cerberea), the Blue Mountains funnel-web (H. versuta) and 12 other species from southern New South Wales and Victoria.

Description The northern tree-dwelling funnel-web spider has a glossy black carapace, and matte black or dark brown chelicerae, legs and abdomen. The dorsolateral surface of the abdomen may have a plum- or purplish tinge. The carapace of both sexes is longer and thinner than other members of the genus Hadronyche. With a body length of 40-50 millimetres, it is the largest member of the funnel-web subfamily Atracinae. The species is very similar to the ground-dwelling Darling Downs funnel-web spider (Hadronyche infensa); the male northern tree-dwelling funnel-web spider distinguished by its knobby spur on the tibia of the second pair of legs, which the male Darling Downs funnel-web spider lacks. Trapdoor spiders are more brown overall in colour. Male and female northern tree-dwelling funnel-web spiders rear up and display their fangs when confronted, drops of venom appearing on the ends of their fangs. They are unable to jump. The venom of the species is potentially deadly to humans, and regarded as the most toxic of those in the family Atracidae. A high proportion of bites—five out of eight recorded cases—from the northern tree-dwelling funnel-web spider result in severe symptoms of envenomation. The venom can be successfully treated with the antivenom for the related Sydney funnel-web spider (Atrax robustus). Symptoms of envenomation can occur within 15 to 20 minutes. Applying pressure bandages and immobilising the patient can significantly delay the onset of symptoms and remains a critical part of the management of an Australian funnel-web spider bite. Despite the venom lacking the δ-atracotoxin or atraxin of A. robustus, the symptoms are very similar to those from a Sydney funnel-web spider bite. Common symptoms include diaphoresis, hypertension, sinus tachycardia, muscle spasm or fasciculation, nausea and vomiting, altered consciousness and local pain at the bite site. Pulmonary oedema occurs frequently and comes on early. As these spiders are larger than the Sydney funnel-web spider, it may be that they inject greater amounts of venom, making the northern tree-dwelling funnel-web spider possibly the deadliest venomous spider species in the world per volume.

Distribution and habitat The northern tree-dwelling funnel-web spider is found in eastern Australia from South East Queensland to the Hunter River in New South Wales. This and the southern tree-dwelling funnel-web spider (Hadronyche cerberea) are the only two species of Australian funnel-web spiders that live predominantly in trees. It lives in rotting logs, branches and hollow furrows and pipes of trees, particularly tallowwood (Eucalyptus microcorys), as well as in epiphytes. They have been recorded in trees 30 m (100 ft) above the ground. Roving males are encountered after rain and at night between late October and early February. They seek shelter during the day.

Ecology The arboreal habitat suggests that wood-boring beetles are a main prey item of the northern tree-dwelling funnel-web spider.

References

External links Data related to Hadronyche formidabilis at Wikispecies Media related to Hadronyche formidabilis at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with Hadronyche formidabilis

Start with the simplest possible case. Write down what Hadronyche formidabilis claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 Hadronyche formidabilis 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 Hadronyche formidabilis 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 Hadronyche formidabilis

In research: Hadronyche formidabilis appears in science 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 Hadronyche formidabilis 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: Hadronyche formidabilis is common in secondary-school and first-year university syllabi. It links to neighbouring topics Arachnids of Queensland, Arthropods of New South Wales, Hadronyche, so understanding it makes those chapters shorter.
In everyday life: Look for Hadronyche formidabilis 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 “Hadronyche formidabilis” →

Affiliate

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

How to study Hadronyche formidabilis in 20 minutes

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

Frequently asked questions

What is Hadronyche formidabilis in simple terms?

Why does Hadronyche formidabilis matter?

Because it connects several science 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 Hadronyche formidabilis?

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 Hadronyche formidabilis.