Insects III Flashcards
How does classification of extant hexapod work?
Not all hexapods are insects, and only pterygotan insects have wings - although wings can be lost
Full metamorphosis is present in a subset of pterygotans
What are the big four insect orders?
Hymenoptera - bees, wasps, sawflies, ants
Coleoptera - beetles
Lepidoptera - moths and butterflies
Diptera - flies and mosquitoes
What are the two groups of hexapods?
`Entognathans - coneheads, springtails, diplurans
Insects - (class insecta - ectognatha) - remaining hexapod diversity
What are features of the entognatha?
name the three orders and
4 features
Coneheads, springtails, dipluran
concealed mouthparts
ametabolous development
eyes reduced/lacking
generally live in soil or litter
Talk about coneheads - protura
600 species in soil, litter, moss, rotting woods, small to v small
biology unknown - some feed on fungal mycorrhizae
first pair of legs directed forward and acting as antennae - sensory
eyes and antennae lacking
Talk about springtails - collembolan
Draw and label a springtail!
9000 species, soil-inhabitants, usually small (2-3mm some up to 12mm)
they have the accolade of being the most diverse non insect hexapods, ecologically important and can reach v high densities in the soil
scavengers, prefers, herbivores
FURCA - springing organ for escaping, retracted under the abdomen when at rest
Eyes reduced or lacking, reduced number o abdominal segments
Talk about diplurans - diplura
1000 species, soil or litter inhabitants 2-5mm
Omnivores, predators, or scavengers
Multisegmented or forceps like cerci (sharps bit at the end) (convergence with earwigs)
No eyes
What are the two Insecta groups?
Insecta have exposed mouthparts
Apterygotans - subclass Apterygota Bristletails, silverfish
Pterygotans - pterygota
Remaining insect diversity
Name 2 features of apterygota and the 2 orders of apterygota
Lack wings in adult stage
ametabolous development
bristletails and silverfish
Talk about bristletails (Archaegnatha)
Draw and label a bristletail
Oldest living insects - wow!
500 species in diverse habitats - 6-25mm
Herbivores (algae, lichens) and scavengers (dead plant material, carrion)
Laterally flattened bodies, monocondylic mandibles (this means it has one point of rotation), large contiguous compound eyes, jumping behaviour (sudden flexion of the abs)
Talk about silverfish
120 species in diverse habitats, 5-30mm
Omnivorous, some herbivores
Dorsoventrally flattened body, dicondylic mandibles, compound eyes reduced or absent NOT contiguous, no jumping behaviour
The mandible has two points of rotation (unlike that of bristletails) - fixed conditions for pterygotans
What are the four monophyletic pterygotan lineages?
Two pairs of wings in adult stage
Paleoptera
Polyneoptera
Paranoptera - these two are known as exopterygota
Holometabola (only one with holometabolous development, rest are hemimetabolous )
Aka endopterygota
Talk about the defining feature of paleoptera and name the two orders
Wings do not fold flat over the abdomen at rest (they are either folded flat to each other or not folded at all)
Mayflies - Ephemeroptera
Dragonflies - odonata
Talk about mayflies please - Ephemeroptera
Oldest living winged insects
3000 species in clean freshwater environments, 2-15cm (med-large)
Nymphs - aquatic, herbivores, detritivores, or predators, respiratory gills present
Adults - aphagous (do not feed) only live a few days, smaller hind wings
Talk about dragonflies - odonata
5500 species in diverse habitats, 2-15cm
Nymphs in aquatic freshwater, predators that hunt with labial mask,
adults- predators, large eyes, tubular abdomens, characteristic mating heart position
What is the defining feature of polyneoptera and name the 10 orders….
Expansion of the posterior region in the hind wing by additional of numerous anal veins - the anal lobe
Angel insects Earwings Stoneflies Grasshoppers Heel walkers Rock/ice crawlers Webspinners Stick and leaf insects Mantises Cockroaches
Talk about angel insects please - Zoraptera
30 species, namely tropical, litter or rotting wood, small <4mm
Live in colonies, fungivores or predatory
Two forms of adults: blind and wingless, eyed and alate (has wings)
Paddle shaped wings with reduced venation
Earwings - dermaptera
Draw earwings!
2000 species near rivers, litter, under bark, small to medium sized 4-25 mm
Mostly non-flying and nocturnal, mostly detritivores, also predators and herbivores
forewing modified in short tegmina that protect highly folded fan shaped hind wings
Forceps-like cercus for defence, offence, mating
Stoneflies - plecoptera
3000 species, 5-50mm
Nymphs, normally aquatic (freshwater), diverse feeding habits
Adults - detritivores or aphagous
Grasshoppers, crickets, and their kin - Orthoptera
and talk about the process of sound production (begins with s) and how this is achieved differently in grasshoppers and crickets
most diverse polyneopteran lineage - 23,000 species in diverse habitats,
2 groups:1) grasshoppers and their kin - herbivores
2) crickets and their kin - predators, herbivores, omnivores
Hind legs adapted to jump. OVIPOSTOR in females
Forewings form hardened tegmina. Fan-like hind wings
Stridulation - sound production by friction leg-wing (grasshoppers) or wing-wing (crickets)
Heel walkers - mantophasmatodea
Most recently discovered insect order - 15 species from afria, 1-2.5cm
Predators living in ground or on vegetation
Apterous, eyes, large, arolium very larg, fore and mid legs raptorial (adapted for seizing prey)
Rock and ice crawlers - grylloblattodea
where are the cool places they are well-adapted for? (clue in name)
25 species in North america and Asia, 2-3.5cm
Scavengers or omnivorous
Well-adapted to cold environments - typically live on ice or snow, caves, alpine soil
Apterous, eyes reduced or absent
Webspinners - embioptera
Describe what is special about webspinners (clue is in the name!)
300 species in litter, under rocks, tree trunks, 2-3.5cm
Detritivores
Live gregariously in silken galleries spun with silk glands present in enlarged foretarsi
Females apterous, males losing wings after dispersal (dehiscent), non-sclerotised wing veins
enlarged foretarsus with silk glands!
Non-sclerotised wing veins
Stick and leaf insects - phasmatodea
what can they do as a defence strategy and what is this called? (begins with a)
3000 species, more diverse in tropics, 3055cm
Phytophagous - feed on plants
Usually cryptic, stick like (elongate, cylindrical), or flattened and often leaf like
Apterous or reduced wings, forewing hardened as tegmina, fan-shaped hind wings,
legs can be shed as defence and regrown in subsequent molts (autotomy)