I can understand that an exo-skeleton will limit how big
a terrestrial insect can be but what is that limit? The largest insects (mass wise) I know of are New Zealand Weta’s which are huge 6-8 inch cricket like creatures.
http://www.bigjude.com/Weta.html
Are there giant “Jurassic” insects that no longer exist?
There was that giant dragonfly with the two-foot wingspan and the one-foot body.
Don’t know exactly if anyone has determined the actual size limit that an insect could get, though.
I don’t know exactly how big Mothra was, but that fucker was big!
http://gnv.ifas.ufl.edu/~TJW/recbk.htm
The above is a link to the University of Florida’s Book of Insect Records. It includes Heaviest Insect (the Goliath beetle, a little under a quarter pound) and the one with the Longest Wingspan (the white witch moth, 11 inches from wingtip to wingtip). There is also Largest Blood Meal for Anne Rice fans.
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On a related topic, this is the largest spider I could find:
http://spiderpharm.com/Selhuwena.htm
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The largest must be fossil ones, since everything else was so big in dinosaur times.
I recall a museum exhibit with a dragon-type-fly that was like 3 foot wingspan, if I remember right. The exhibit was on amber formation, so maybe parts were found.
YEs the Goliath beetle is the current record holder, although there was indeed a dragonfly back in the day with a two foot wing span. 2 things limit insect size (as well as that of Spiders and similar critters)…those being the weight of the insect internally is poorly supported by the exoskeleton…thus their own weight would crush them if they got too big…also they have an open circulatory system (meaning the fluids simply diffuse through tissue without arteries per se) which does not function well in big critters. The limits of such a design are probably more notable in the ocean where water supports some of the weight…thus crabs and lobsters can get much bigger than land based insects.
Back in those days, we had dragonflys that were 12" long? How did they survive? I heard something (maybe in “JRASSIC PARK”) that the air had more oxygen then.
Serously-could we re-create the dragon flys of old, ala Jurassic Park? We have all the necessary genetic material-all we have to do is trick the gene into making a giant version!
is this possible?
Don’t forget that insects don’t have lungs or gills and respire through tracheae. This also limits their size. Crustaceans and most Arachnids don’t suffer from this limit.
Ooo… 100 posts! 
Goliath???:
The largest prehistoric insect was the dragonfly Meganeura monyi, that lived about 300 million years ago.
Fossil remains (impressions of wings) discovered at Commentry, France indicate a wing extending up to 70 cm
27 1/2 in.
United States The giant green darner (Anax Walsinghami), found in the western states, has a body length of up
to 4 1/2 in.
The world’s largest-known spider is the goliath bird-eating spider (Theraphosa leblondi) of the coastal
rainforests of Suriname, Guyana (formerly British Guyana) and French Guiana, northeastern South America;
isolated specimens have also been reported from Venezuela and Brazil. In February 1985 Charles J.
Seiderman of New York City, NY, captured a huge female just north of Paramarido, Suriname. This spider
had a maximum leg span of 266.7 mm 10 1/2 in (total body length 102 mm 4 in), 25 mm 1 in long fangs and
weighed a peak 122.2 g 4.3 oz before its death from moulting problems in January 1986. An outsized male
example collected by members of the Pablo San Martin Expedition at Rio Cavro, Venezuela in April 1965 had
a leg span of 280 mm 11.02 in; the female is built on much heavier lines. United States The Rhecosticta
california, a type of tarantula, found in the Southwest, is the heaviest spider and has the longest body.
However, the orb web spider (Nephila clavipes) of the family Araneidae, found in the southern Gulf States,
and the wolf spider (Lycosa carolinensis) of the family Lycosidae, found in the Southeast, equal its leg span.
We do? That’s news to me. I can see two things you may mean:
Normal dragonfly DNA is sufficient to make giant dragonflies with a little help, like maybe a hit of plutonium. Nope. You’re talking about completely restructuring the entire body. Major major manipulations here. We would need DNA from giant dragonflies, so I will assume you mean:
We have giant dragonfly DNA from amber fossils, a la Jurassic Park. If you are aware of a specimen, I’d love to get ahold of it and see what we can do. I don’t think there are any two foot long anythings in amber anywhere. And even if there were, extracting DNA is more complicated than the movie made out.
Sorry.
I need bigger shoes.
handy said:
And this arachnophobic individual will now, officially, require therapy.
(Note to self: Steer clear of the Southern Hemisphere …)