True bugs are suckers
A true bug’s an insect
but insects aren’t bugs
if they eat by chomp-chomp
instead of glug-glug.
Ants are not bugs.
They’ve got mandible jaws.
While a bug’s beaky tube
will get used like a straw.
Bugs feed on liquids
like plant-juice or blood
by piercing the skin
and then sucking, glug-glug.
Cicadas and bed-bugs
are glug-sucking guys.
But ladybird beetles
aren’t bugs – so get wise!
First published in Double Helix (September 2016)
Reproduced with permission of CSIRO
True bugs (Order: Hemiptera)
Including shieldbugs, plant bugs, bed bugs, pondskaters, cicadas, water bugs, aphids and scale insects.
The Hemiptera are called ‘true’ bugs because everyone – entomologists included – tend to call all insects ‘bugs’. That is a loose term, whereas the true bugs are just those contained within the insect order Hemiptera.
This group of insects is very large, with around 75,000 species worldwide. Around 1,700 of these can be found in the British Isles. Many of them are very different from each other, but all of them have piercing mouthparts with which they can suck the juices from plants or animals – usually plants. Their mouthparts are contained in a beak (or rostrum) which is usually held underneath the body when not in use.
As plant feeders, some bugs – such as the aphids, for example – are serious agricultural pests, not just because they damage crops but because they can transmit viral diseases too. However, most bugs are not pests.
The true bugs often have long antennae divided into a small number of segments, and the front wings can be somewhat hardened. Some bugs resemble beetles, but beetles have wing covers that do not overlap, unlike the bugs.
Bugs undergo incomplete metamorphosis – their life cycle stages include the egg, adult-like nymphs, and winged adults.
Hemiptera: bugs, aphids and cicadas
The insects in this order are extremely diverse in their size, shape and colour. There are about 6000 described species in Australia, ranging in size from 1 to 110 millimetres in length. The name Hemiptera means ‘half wing’ and all hemipterans share the following features:
The young of hemipterans look like small adults. Some bugs may be mistaken for beetles but can be distinguished by their mouthparts as beetles have mandibulate mouthparts while bugs have sucking/piercing mouthparts.
Most species of Hemiptera are plant feeders, sucking sap with many causing considerable damage to crops, ornamental garden plants such as roses, shrubs and trees. Some species are bloodsuckers of mammals and birds while others are predators that feed on other invertebrates, including some pest species and are therefore beneficial to man.
What is a bug? It’s not something you come down with. (A bacterium is not a bug; a virus is certainly not a bug.) A bug is not any old thing that crawls. It’s not a tick, not a mite, not a gnat. A ladybug is not a bug. (It’s a beetle.) Certainly, a butterfly is not a bug. Bug, it turns out, is a technical term: “true bugs” are insects in the order Hemiptera.
The stinkbug is a true bug. So are the squash bug, the toad bug, the red bug, the seed bug, the box elder bug, and the assassin bug. Assassin bugs capture their insect prey with sticky front legs and stab them with their little beaks. There are ambush bugs. Ambush bugs sit like statues on flower petals, waiting, waiting … Waterbugs are true bugs. The bedbug is a bug. Ugh.
Besides being an insect with the usual six legs and three main body divisions—head, thorax, and abdomen—bugs have sucking, beak-like mouth parts and their life cycle occurs in a pattern called “incomplete metamorphosis.” They go from egg to nymph (a baby that looks like a small adult) to adult, with no larva stage.