Extreme Insects. Richard Jones

tenebricosa, which oozes out a great drop of bright-red liquor from its mouthparts.

      Ladybirds are brightly coloured to emphasise the warning. Timarcha is a sombre black, but its colouring is equally obvious against the green of its meadow foodplants. This large, lumbering flightless leaf beetle has little to fear from predators and it feeds quite happily in broad daylight.

Most beautiful insect

NAME	birdwing butterfly, in particular Wallace’s golden birdwing Ornithoptera croesus
LOCATION	Batchian (Bacan), Indonesia
ATTRIBUTE	beautiful enough to cause one of the world’s most hardened travellers nearly to faint

      Beauty is very much in the eye of the beholder; just look at some of the names cooked up by entomologists. Scientific names regularly include terms such as formosa (handsome), splendidissima (most splendid), pulchrina (beautiful), nobilis (noble), venustus (lovely) and elegans (elegant).

      There are many insects worthy of the title ‘most beautiful’, but nowhere is this better described than in the words of Victorian naturalist, scientist and traveller Alfred Russel Wallace. In a time before research grants, Wallace financed his travels by making collections for wealthy patrons or selling the handsome and strange specimens when he returned home to Britain. The highest value specimens were fabulous birds of paradise and beautiful birdwing butterflies. He knew only too well the worth of his collections. On the morning of 6 August 1852, during his return across the Atlantic from South America, the ship on which he was travelling, the Helen, caught fire and sank. Wallace and the crew spent nine days in the open life boats before they were rescued, but all Wallace’s specimens were lost.

      Undeterred, he published his Travels on the Amazon and Rio Negro and was soon off exploring and collecting in Southeast Asia. He managed to bring his booty home safely this time, and captured the essence of exploration, discovery and the hunt for fantastical beasts in Malay Archipelago, published in 1859. On his first venture into the forests of Batchian (now Bacan), one of the Mollucan islands of Indonesia, he caught sight of a spectacular birdwing butterfly. It took him a further two months to finally collect a specimen. Wallace later named it Ornithoptera croesus, after the 6th-centuryBCE king of Lydia (now part of Turkey) famed for his wealth. Wallace’s words still resonate today:

      ‘The beauty and brilliancy of this insect are indescribable, and none but a naturalist can understand the intense excitement I experienced when I at length captured it. On taking it out of my net and opening the glorious wings, my heart began to beat violently, the blood rushed to my head, and I felt much more like fainting than I have done when in apprehension of immediate death. I had a headache the rest of the day, so great was the excitement produced by what will appear to most people a very inadequate cause.’

Longest head

NAME	giraffe-necked weevil Trachelophorus giraffa
LOCATION	Madagascar
ATTRIBUTE	the longest head of any insect

      It will come as no surprise to discover that some males have big heads. Big heads can be attached to big jaws (see page 60) or house big eyes (see page 56). But the male giraffe-necked weevil of Madagascar has the most awkward-looking head imaginable. And what does he use it for? Nodding.

      The male’s long, slender head takes up about 10 of his 25 mm (1 in) length. The neck is another 7 mm, making the insect’s head and neck over 70 per cent of its entire body length. It holds them angled up from its squat body, like a miniature construction site crane. The female’s head and neck are also relatively long, but only about half her total body length.

      The male uses his stretched form for no practical purpose. The nodding, however, is very important to other giraffe-necked weevils. It seems that the males contest one another, trying to out-nod their opponents in ritualised fights. After head-to-head nodding competitions, one male will retreat. It also appears that the females choose the best nodders with which to mate. Thus, over evolutionary time, the males with the longest heads (better for nodding) have been selected.

      The irony is that it is the female who really needs a long head. Trachelophorus belongs to a group of beetles called leaf-rolling weevils. She chews through both sides of a leaf blade to the mid-rib. The leaf now has a tendency to curl, a property that she harnesses using her angled neck and head to roll the partly severed plant into a small cigar. She lays an egg inside, and the grub is protected from predators and parasites while it feeds.

Most streamlined insect

NAME	water pennies in the family Psephenidae
LOCATION	worldwide
ATTRIBUTE	shaped to withstand rushing torrents

      Despite rolling boulders and white water, life continues beneath the surface of fast-flowing rivers. There, attached to the stones in the water, live water pennies. So named because they are roughly the size of a one-cent coin (a penny), these creatures are the larvae of beetles. The adult beetles are terrestrial, but their larvae are wholly aquatic.

      A water penny is multi-segmented, with each segment flattened into a flange that surrounds its body, hiding head, legs and gills beneath a smooth carapace. It clings tight to rocks and stones using its clawed feet. If it cannot get a purchase, then even slow-moving water can wash it away. The larvae spend most of the time under stones or pressed into small cracks in the rocks, feeding on microscopic algae. But they must leave the water to pupate, and at such times they are exposed to the force of the water.

      In rapidly moving water, there is a boundary layer of calmer water at the bottom, slowed by friction with the river bed. Small and flattened, water pennies can sit within this layer, but they cannot afford to be complacent. As well as clinging on tight with their feet, they use hydrodynamics to hold fast. By pumping water out through the gaps between their segments and at the tail end of the body, they can reduce turbulence to creep slowly through the force of the flow.

Loudest insect

NAME	dog day cicada Tibicen pronotalis
LOCATION	North America
ABILITY	makes the loudest noise of any insect

      Insects are generally