50 Fun Facts About Spider

Spiders belong to which order?

They are the largest order of arachnids and rank seventh in species diversity among all orders of living things.

Which is the only continent with no spiders?

They have adapted to almost every habitat elsewhere, from mountaintops to one species that lives underwater.

Unlike insects, spiders lack which sensory feature on their heads?

They also have their body segments fused into just two parts, the cephalothorax and the abdomen, joined by a narrow pedicel.

How do spiders extend their legs, since they have no extensor muscles?

That is why a dead spider's legs curl inward: the pressure is gone.

Which spider, named for a Jungle Book character, was described in 2008 as the only mostly herbivorous one?

It lives on Central American acacias and eats their protein-rich Beltian bodies; every other known spider is a predator.

Roughly how much prey do the world's spiders eat each year, according to one estimate?

That is from an estimated 25 million tons of spiders, more animal weight than all humans eat in meat and fish combined.

Spider silk is spun from spinnerets fed by up to how many types of gland?

Different glands make dragline, capture, egg-case and wrapping silks; the spiral orb web may be one of the oldest designs.

In which property does dragline spider silk beat both steel and Kevlar?

Toughness means energy absorbed before breaking; silk's stretchiness is what makes it so hard to snap.

Darwin's bark spider, discovered in Madagascar in 2009, holds what record?

Its silk is the toughest biological material ever studied.

Which is the world's largest spider by mass and body length?

A tarantula of northern South America; the giant huntsman of Laos beats it on leg span at 25-30 cm.

Patu digua, from Colombia, is by some accounts the smallest spider. Males are about the size of what?

Its body measures around 0.37 mm.

Which family, with about 7,000 species, is the largest of all, making up 13% of the order?

They have some of the best vision of any arthropod, with stereoscopic colour sight, and use it for hunting and courtship.

Which salticid genus is famous for eating its own kind and improvising hunting tactics?

Its members remember tactics that worked, a level of problem-solving normally credited to much bigger animals.

The dancing peacock spiders of the genus Maratus are native to which country?

They are tiny, mostly 4-5 mm; only the males wear the iridescent 'plate'.

Which is the only species known to live almost entirely underwater?

Argyroneta aquatica eats, mates and lays eggs in an air-filled silk bell, surfacing only to top up its oxygen.

Bolas spiders catch moths by doing what?

They lure male moths in with up to three fake sex pheromones, then reel them in like an angler.

What is the name for the way small spiders travel by releasing fine threads and riding the wind?

A 2018 study found the Earth's electric fields alone can lift them; sailors have found spiders far out to sea.

Which two spiders are the only ones in North America with venom considered dangerous to people?

Recluse spiders can be told apart by having six eyes in three pairs rather than the usual eight.

How many eyes does a brown recluse have, unlike most spiders?

They sit in three pairs; the violin mark on its back is not a reliable identifier because other spiders have it too.

Black widows, redbacks and the New Zealand katipō all belong to which genus?

Its neurotoxin latrotoxin causes latrodectism; the genus has 34 species including South Africa's button spiders.

The Australian redback is one of a number of spiders that usually do what while mating?

Females store sperm for up to two years and lay clutches averaging 250 eggs.

Since an antivenom arrived in 1981, how many people have died from Sydney funnel-web spider bites?

A 1927 death of a boy in the suburb of Thornleigh first made the species notorious.

Who first described the Sydney funnel-web in 1877, naming it Atrax robustus?

He worked from a female specimen in the British Museum; robustus is Latin for sturdy.

The word tarantula originally referred to a wolf spider named after which Italian town?

Lycosa tarantula of the Mediterranean gave its name to the frenzied tarantella dance; the name later stuck to the big hairy Theraphosidae.

Roughly how many tarantula species have been identified in the family Theraphosidae?

They span almost 200 genera; New World species defend themselves with irritating urticating hairs.

Wolf spiders carry their egg sacs how?

Once hatched, the spiderlings ride on their mother's back; nursery web spiders, by contrast, carry sacs in their chelicerae.

Male giant huntsman spiders in Laos reach a leg span of about how much?

That is the widest of any spider, though the Goliath birdeater is heavier.

Which two spider families have lost their venom glands and kill prey with silk instead?

Almost every other spider injects venom through fangs at the tips of its chelicerae.

Arachnophobia affects roughly what share of the world's population?

It is one of the most common anxiety disorders, though most arachnids pose little threat.

In Ovid's Metamorphoses, the weaver Arachne becomes a spider after challenging which goddess?

The Lydian maiden was credited with inventing linen cloth and nets; her name gives us 'arachnid'.

In E. B. White's Charlotte's Web, what is the first phrase Charlotte weaves to save Wilbur?

The 1952 book, illustrated by Garth Williams, gives the spider the full name Charlotte A. Cavatica, after the barn spider's Latin name.

Little Miss Muffet, frightened away by a spider, was eating what?

The rhyme was first printed in 1805; what exactly a 'tuffet' is has been argued about for over a century.

Spiders' fangs are the final sections of which appendages?

Scorpions' chelicerae have three sections and no fangs; spiders' have two, folding away when not in use.

Which is the most primitive living group of spiders, lacking a fully centralised nervous system?

All other spiders have every ganglion fused into one mass in the cephalothorax, the most centralised nervous system of any arthropod.

Most spiders excrete nitrogen waste as what dry substance, saving water?

Malpighian tubules extract it from the blood; the same trick lets many desert spiders survive without drinking.

What are the sheet-like breathing organs found in tarantulas and other primitive spiders called?

Mygalomorphs have two pairs; many modern spiders use a tracheal system instead, or both.

What is the narrow waist joining a spider's cephalothorax to its abdomen called?

It lets the abdomen move independently while spinning silk.

Which is more abundant and diverse: spiders that spin spiral orb webs, or those that make tangled cobwebs?

The orb web may nonetheless be one of the earliest web forms to evolve.

Female spiders lay their eggs in what?

A single case may hold hundreds of eggs, and mothers of many species guard or carry them.

Why do male spiders perform elaborate courtship rituals?

Males of most species survive a few matings, limited mostly by their short lifespans.

Spider silk genes have been inserted into which organisms in the search for mass-produced silk?

Researchers are also studying spider venom for medicines and non-polluting pesticides.

Which spider family are wolf spiders, named for their hunting prowess and excellent eyesight?

They hunt alone, mostly without webs, pouncing on prey or ambushing from burrows.

Which chelicerate group do spiders belong to, alongside scorpions?

Arachnids have two body sections and eight legs; ticks, mites and harvestmen are also arachnids.

The vegetarian salticid feeds on Beltian bodies, nutritious nubs produced by which trees?

It lives on Vachellia acacias in Mexico, Costa Rica and Guatemala, dodging the ants that guard them.

Which is the largest order of the eight-legged chelicerate class?

They rank seventh in species diversity among all orders of organisms.

What is the especially fine silk that airborne spiders use to lift off called?

The word is now used for any exceedingly fine thread or fabric.

Salticids breathe using what combination?

This bimodal breathing supports their agile jumps and their exceptional eyesight.

The world's heaviest tarantula lacks which structure found on most adult males' front legs?

It lives in deep burrows in the swampy rainforests of Suriname, Guyana, French Guiana and northern Brazil.

Which two-word Latin name belongs to the underwater bell-builder, the only member of its genus?

Some Desis species also shelter underwater at high tide in silk retreats.

Besides the panther one, which two Kipling-named salticid genera did the Peckhams coin in 1896?

Messua was a fourth; the Peckhams were pioneering American arachnologists.