Hexapoda

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Hexapoda 2 (insects)
Click here for Insect records, Flight data , Insects as Vectors of diseases in humans, 4 main functions of a sense of smell in insects , insects as pollinators, behaviour patterns, ID.

--Centipedes

--Hexapoda 1 (insects)

--Hexapoda 2 (insects)

--Identification to order level

--Insect orders

----Lepidoptera (butterflies, moths)

----Ephemeroptera (mayflies)

----Hemiptera (bugs, cicadas)

----Hymenoptera (bees, ants, wasps & saw flies)

------Bumblebees

----Coleoptera (beetles)

----Dictyoptera (mantids, cockroaches)

----Diptera (true flies)

----Neuroptera (lacewings, ant lions)

----Orthoptera (crickets, locusts)

----Thysanura (bristletails, silver fish)

----Strepsiptera (stylops)

----Thysanoptera (thrips)

----Odonata (dragonflies, damselflies)

----Trichoptera (caddis flies)

----Siphonaptera (fleas)

----Isoptera (termites)

----Phasmida (stick & leaf insects)

----Dermaptera (earwigs)

----Anoplura/siphunculata (sucking lice)

----Mallophaga (biting lice, bird lice)

----Psocoptera (book, bark, dust lice)

----Mecoptera (scorpion flies)

----Collembola (springtail)

----Embioptera (web spinners)

----Plecoptera (stone flies)

----Diplura (bristletails)

----Protura

----Zoraptera

Cimex lectularius, bed bug

The Apterygote (wingless) Classes

These are the Diplura (bristletails), Collembola (springtails), Protura and Thysanura (silverfish).
The bristletails and silverfish both have two long cerci, and between this a caudal appendage. There are just under 10 000 described species of Apterygotes.

Class Pterygota (winged) Classes

The insects in this class have two pairs of wings; one pair on the mesothorax and another on the metathorax. The Pterygotes can be further divided into two groups; those that undergo complete metamorphosis (holometabolous). A typical holometabolous insect the brown house moth, Hofmannophila pseudospretella shown below in the various stages of its life. And those that undergo a gradual metamorphosis (hemimetabolous). Hemimetabolous insects have young that resemble the adults, and the gradual

development of wings is external . Such insects include, Cimex lectularius (the bed bug) on the left which shows the gradual change to the adult form, also Odonata (dragonflies), Orthoptera (grasshoppers), Dermaptera (earwigs) and Hemiptera (aphids, cicadas. Pterygotes have muscles which allow them to close their spiracles so greatly reducing water loss and enabling them to colonise drier habitats.

Holometabolous insects have young (larva) that usually do not resemble the adult (see right), and often occupy a different niche. These insects form a pupa (see right) before emerging as the adult form.

About 88% of the described insects are holometabolous and include the four largest Orders that have diversified along with the diversification and radiation of the Angiosperms; they are the Diptera (flies), Coleoptera (beetles), Hymenoptera (wasps, ants, bees), and Lepidoptera (butterflies and moths).

Hofmannophila speudospretella, brown house moth

Insects as vectors of diseases in humans
Disease	Insect vector
Malaria	Anopheles mosquito (Diptera)
Yellow fever	Aedes aegypti Mosquito (Diptera)
Filariasis	Culex mosquito (Diptera)
Typhoid	House fly (Diptera)
Dengue	Aedes mosquito (Diptera)
Sleeping sickness	Tsetse fly (Diptera)
Plague	Fleas (Siphonaptera)
Typhus fever	Louse (Anoplura/Siphunculata)
Chagas	Rhodnius (Hemiptera)

Insects as pollinators.

In the US alone insect pollinated crops were worth $20 billion at 2000 prices.
Every third mouthful of food we eat comes directly or indirectly from crops that have been pollinated by bees.

Insect records

Fastest flight	Austrophlebia costalis (Odonata: Aeshnidae), a dragonfly at 98 km/h Hybomitra hinei wrighti (Diptera: Tabanidae), a fly at 145 km/h
Fastest wing beat	Forcipomyia sp. (Diptera:Ceratopogonidae), a midge, species not known can beat its wings 1046 times per second.
Fastest runner	Cicindela hudsoni, an Australian tiger beetle can run at 2.5 metres per second.
Least specific vertebrate blood sucker	Glossina palpalis (Diptera: Glossinidae), tsetse fly. It can feed on any vertebrate.
Longest	Pharnacia serratipes, a stick insect, at 55.5 cm (22 in).
Smallest adult	Dicopomorpha echmepterygis (Hymenoptera: Mymaridae), a parasitic wasp. The length of the male is 139 µm.
Largest swarm	Schistocerca gregaria, the desert locust. In 1954 a swarm covering 200 km sq invaded Kenya. The swarm was estimated to contain 10 billion individuals.
Largest eggs	Xylocopa auripennis, a carpenter bee lays eggs 16.5 mm long and 3.0 mm in diameter.
Heat tolerant	Cataglyphis bicolor (Hymenoptera: Formicidae), a Saharan ant which can forage at body temperature above 50^oC and surface temperature of up to 70^oC.
Cold tolerant	Polypedilum vanderplanki (Diptera), an African chironomid(midge) can survive submersion in liquid helium at -270^oC.
Most spectacular mating	Apis mellifera (Hymenoptera), the honey bee. The drone (male) dies after mating once. The queen bee files off with his phallus still in her vagina. The phallus having broken off after sperm exits explosively. The queen eventually ejects the phallus and goes on to mate again.
Longest regular migration	Danaus plexippus (Lepidoptera: Danaidae), the monarch butterfly. Some migrate more than 4000 km from Southern Canada to Central Mexico.
Longest adult life	Lasius niger, ant queen survived 28.75 years in captivity. Pogonomyrmex owyheei, ant queen, 30 estimated in the wild.
Longest life cycle	Buprestis aurulenta larva, a wood boring beetle, emerged after 51 years
Shortest adult life	Dolania americana (Ephemeroptera), a mayfly, lives for less than five minutes after her final molt. During the five minutes she chooses a mate, mates, and lays her eggs.
Shortest generation time	Rhopalosiphum prunifolia, an aphid, has the shortest generation time of 4.7 days at 25^o C.
Most polyandrous (female with highest number of mates)	Apis dorsata (Hymenoptera:Apidae) a queen bee mated 53 times, each with a different male. Chrysochus cobaltinus (Coleoptera: Chrysomelidae), a blue milkweed butterfly female, had up to 60 matings, though some of these were multiple matings with the same male.
Loudest	Brevisana brevis (Homoptera: Cicadidae), a cicada, produces a calling song with a mean sound pressure level of 106.7 decibels at a distance of 50 cm.
Best "new" man	Male Nicrophorus orbicollis, a burying beetle, participate in all activities, remain with the brood throughout development, and can take over all parenting responsibilities if the female disappears.
The above insect records, taken from Walker, T.J., ed. 2001. University of Florida Book of Insect Records, 2001.
Fastest muscles	Termes panamensis, (a termite) has the fastest muscles in the world. It needed film shot at 40 000 frames per second to calculate the speed at which T. panamensis snaps its jaws shut, and the result is 70.4 m s-1. Its jaw muscles are so big that they fill half the space inside its head, and they are triggered by seeing an intruder's face inside the nest.
Longest sexual intercourse	In many stick insect species males are never or hardly ever seen, however in other species the males can maintain intercourse for months at a time.

Flight data from some insects (from various sources)
Insect	Speed metres per second	Wing beats per second
Scorpion fly	0.5	28
Field grasshopper	0.5
Mosquito	0.9
Damselfly	1.5	16
Stag beetle	1.5
Ammophila wasp	1.5
House fly	2.0	190
Common wasp	2.5
Large white butterfly	2.5	12
Honey bee	2.5	250
Monarch butterfly	2.8
Bumblebee	3.0-4.5	130-240
Cockchafer	3.0	46
Hoverfly	3.5	120
Horse fly	4.0	96
Desert locust	4.4
Hummingbird hawk moth	5.0	85
Hornet	6.0	100
Dragonfly	7.0	38
Fruit fly (Drosophila)		300
Midge (Scottish)		>1000
Swallowtail butterfly		5

4 main functions of a sense of smell in insects, plus examples
Sexual attraction	Gathering of male moths to a female releasing a pheromone
Recognition of nest mates	Ants, bees and wasps recognise nest mates and intruders. Ants lay down trails between nest and food source.
Egg laying attractants	Blowflies and carrion beetles are attracted to rotting meat as this provides a food source and habitat for larvae.
Food attractants	Dung beetles attracted to the smell of dung as a food source and also as an egg laying site.

Insect behaviour patterns.

Courtship. This usually involves males trying to attract females. The female behaviour is simply to accept or reject, e.g. during courtship the male scorpion fly presents the female with a dead insect which she eats during copulation.

Copulation. Copulation is the physical joining of the male and female culminating in the passing of sperm from the male to the female, e.g. bumblebees.

Egg-laying. Most species have very specific site requirements for egg-laying, so that the eggs are laid on, in or near the source of food for the larva or nymph, e.g. dung beetles.

Defence. Defence can be active, e.g. sting (bees, wasps, etc.), bite (beetles, etc.), chemicals (bombadier beetle); or passive e.g. hiding (cockroach), camouflage (stick insect).

Communication. Communication is the transfer of information between individuals - usually of the same species, e.g. honeybees communicating the location of a good food source.

Grooming. This is especially important in hairy insects, e.g. bumblebees. These and all others need to keep their antennae, eyes, wings, legs and mouthparts clean. Most have a brush or comb on their forelegs, e.g. bumblebees, that can be used to cleans antennae and legs.

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