Transcript Prey - NGHS

Insects
External
Anatomy
Adult insects are known for having three major body regions,
six legs, one pair of antennae and usually two pair of wings as
adults.
head
thorax
abdomen
Adult insects develop as a composite of fused segments
with specific body part associations.
from the 1995 Physiology or Medicine Nobel Poster
HEAD
antennae
compound
eyes
The first body
region is the head.
Insect heads can be
highly variable, but
most possess eyes,
antennae and
mouthparts.
head
mouthparts
Antennae
beetle
butterfly
ant
fly
termite
June beetle
Antennae are used by insects as major sensory
devices, especially for smell, and can be adaptive
for the insect in many ways.
Two Examples of Mouthparts
chewing
piercing/sucking
Insect mouthparts are also highly modified for the
insect. Chewing, biting, or sucking, are a few examples.
Mouthparts of an immature insect may differ from those
of the same insect in its adult stage.
Arthropod Vision
• Simple eyes
– Light sensitive
cells share a
common lens
• Compound eyes
– Thousand of
closely packed
units called
ommatidia
Simple ocelli.
Complex lensed ocelli.
Compound eyes made of ommatidia.
Compound & Simple Eyes
Picture of bodyparts
The middle body region is
called the thorax and is
composed of three fused
segments. All legs and
wings are located on the
thorax.
Thorax
swimming
digging
suction
Legs
grasping
Like the mouthparts and
antennae, insect legs are quite
variable in form and function
and reflect the insect's lifestyle.
Walking
Walking involves the coordinated
movement of uniramous
appendages in different planes.
Walking
Subphylum Myriapoda Millipedes (Class
Diplopoda) have
two legs per
segment on each
side. Slow but
powerful.
Centipedes (Class
Chilopoda) have
one leg per
segment on each
side. Fast but not
as powerful.
Flying
Hemipterans (flies)
Indirect flight muscles allow wings to beat faster than
neural transmission.
Dorsoventral and longitudinal muscles.
Flexible thorax.
The last body region is
called the abdomen. It is
composed of many
segments connected by
flexible sections allowing it
great movement.
Abdomen
Insects possess an exterior covering called the
exoskeleton. They do not have internal bones. This
segmented "shell" is what gives insects shape and can
be very hard in some insects. It is often covered with a
waxy layer and may have "hairs" called setae.
seta ( hair)
waxy layer
Exoskeleton x-sec
Internal
Anatomy
Inside the insect we find the systems for respiration,
circulation, nerves, and digestion, but there is little
resemblance to the same systems found in man or other
mammals.
Digestive System
foregut
hindgut
Digestive sys
midgut
The digestive system is a tube that opens at the mouth and empties
at the tail end of the insect. It is divided into three parts called the
foregut, midgut, and hind gut. In some insects such as the honey
bee, the foregut acts as a crop to carry or hold liquids which can be
regurgitated later.
Circulatory System
“ heart ” aortic pumps
Circ system
The circulatory system is not composed of a central heart, veins and
arteries which circulate blood cells and transport oxygen. The
insect circulatory system is a simple tube down the back which is
open at both ends and slowly pulses body fluids and nutrients from
the rear of the insect to the head.
Insects have a less centralized nervous system than humans. The
nerve chord runs along the ventral or bottom aspect of an insect.
The brain is divided into two main parts. The largest lobes control
important areas such as the eyes, antennae, and mouthparts. Other
major concentrations of nerve bundles called ganglia occur along the
nerve chord and usually control those body functions closest to it.
two lobed brain
Nervous system
nerve bundles (ganglia)
Nervous System
The respiratory system is composed of air sacs and tubes
called tracheae. Air enters the tubes through a series of
openings called spiracles found along the sides of the body.
The largest spiracles are usually found on the thorax
where greater musculature from wings and legs require
more oxygen. There are no spiracles on the head.
spiracles
Respiratory
System
tracheal
tubes
“Brain” is 2-3 ganglia with
specific functions.
Ganglionated ventral nerve cord.
Sense organs (sensilla) protrude
out of cuticle.
Can be slit in cuticle.
Membranous drums.
Chemoreceptors with thin cuticle.
How do Arthropods reproduce and develop?
Most gonochoristic with formal mating and internal fertilization.
Life
Cycles
The many diverse orders of insects have four different types of life
cycles. These life cycles are called "metamorphosis" because of the
changes of shape that the insects undergo during development.
egg
Without Metamorphosis
nymphs
adult
Without meta
The first type is "without" metamorphosis which the
wingless primitive orders such as silverfish
(Thysanura) and springtails (Collembola) possess. The
young resemble adults except for size.
Incomplete Metamorphosis
egg
naiads
adult
Incomplete meta
The second type is "incomplete" metamorphosis
which is found among the aquatic insect orders such as
mayflies (Ephemeroptera) and dragonflies (Odonata).
Gradual Metamorphosis
The third type is "gradual" metamorphosis seen in such orders as the
grasshoppers (Orthoptera), termites (Isoptera), thrips (Thysanoptera)
and true bugs (Hemiptera). This life cycle starts as an egg, but each
growth, or nymphal stage looks similar, except it lacks wings and the
reproductive capacity that the adult possesses.
egg
nymphs
adult
Complete Metamorphosis
The fourth type is "complete" metamorphosis found in butterflies
(Lepidoptera), beetles (Coleoptera), flies (Diptera), and bees, wasps,
and ants (Hymenoptera). This life cycle has the four stages of egg,
larva, pupa, and adult. Each stage is quite distinct.
egg
larvae
pupa
adult
It should be noted that because insects are hard-bodied,
they cannot grow larger gradually. Instead they grow
larger in steps by shedding the hard exoskeleton for a brief
period of expansion. The brief periods between or within
stages are called molts. Insects are soft-bodied and
vulnerable during this time.
recently molted roach
Molting
• Secretion of "molting
fluid" to dissolve old
endocuticle.
• New cuticle formed
under old exocuticle.
• Break out of old
cuticle
– Old cuticle breaks at
line of weakness
Growth stages
• Arthropod passes
thru 3-20+ growth
stages in life cycle.
• Some stop molting
as adults (insects,
most spiders)
• Some continue to
molt (crayfish,
tarantulas)
Soldier Beetles
Order Coleoptera
Family Cantharidae
David Laughlin
Life History: Adults
on flowering shrubs
and trees. Larvae
in soil.
Prey: Aphids, locust eggs, snails, slugs,
millipedes, earthworms, caterpillars, and
maggots.
Ground Beetles
Order Coleoptera
Family Carabidae
Life History:
Nocturnal, in or on
soil, some live up to
four years.
Prey: Caterpillars,
soil and tree insects,
earthworms.
Top: Harpalus sp.
Bottom: Calosoma sp.
Vera Krischik
Tiger Beetles
Order Coleoptera
Family Cicindellidae
Life History:
Stalking
predators,
fast runners.
Prey: Whatever
they can catch.
John Davidson
Rove Beetles
Order Coleoptera
Family Staphylinidae
Life History: Nocturnal predators.
Prey: Soil-dwelling insects.
Lady Beetles
Order Coleoptera
Family Coccinellidae
Life History: Many
species, both larvae
and adults are
predaceous.
Jeff Hahn
Prey: Aphids, scale
insects, mealybugs,
whiteflies, spider
mites, insect eggs.
Pink Lady Beetle (Coleomegilla
maculata), a native lady beetle
Convergent Lady Beetle
Order Coleoptera
Family Coccinellidae
Hippodamia
convergens
Life History: Native
and common in the
Midwest; larvae and
adults are both
predaceous.
Prey: Aphids.
John Davidson
Multicolored Asian Lady Beetle
Order Coleoptera
Family Coccinellidae
Harmonia axyridis
John Davidson
Life History: Introduced, invades homes in fall.
Prey:
Aphids
and
scales.
John Davidson
John
Davidson
Robber Flies
Order Diptera
Family Asilidae
Whitney Cranshaw
Life History: Larvae
live in soil and
decaying wood;
adults are fast fliers.
Prey: Butterflies, wasps, bees, dragonflies,
grasshoppers, beetles, and other flies.
Larvae feed on soft-bodied insects such as
grasshopper eggs, white grubs, and other
insect larvae.
Gall Midges
Order Diptera
Family Cecidomyiidae
Life History: Tiny adults
feed on honeydew and
nectar, larvae are
predaceous.
Prey: Larvae feed on
aphids, mites, scales,
whiteflies, and thrips.
Whitney Cranshaw
Top and bottom: Aphidoletes aphidimyza feeding on aphids
Syrphid or Hover Flies
Order Diptera
Family Syrphidae
Life History: Adults
feed on nectar and
pollen. Larvae are
predaceous. One generation every 2 to 4
weeks.
David Laughlin
Prey: Larvae feed on aphids, scales, and
other insects.
Tachinid Flies
Order Diptera
Family Tachinidae
John Davidson
Life History: Adults
lay eggs on plants or
hosts. Larvae develop
inside hosts and pupate in 4 to 14 days. One
or more generations per year.
Prey: Caterpillars, adult and larval beetles,
sawfly larvae, true bugs, grasshoppers, and
others.
Minute Pirate Bugs
Order Hemiptera
Family Anthocoridae
Life History: One
generation takes
20 days to complete,
multiple generations
per year.
Orius insidiosus adult
Prey: Spider mites, insect eggs, aphids,
thrips, scales, caterpillars.
Seed and Big-Eyed Bugs
Order Hemiptera
Family Lygaeidae
Life History: Many
Lygaeids feed on plants,
but some are predaceous.
Prey: Insect eggs, aphids,
mealybugs, spider mites,
leafhoppers, plant bugs,
whiteflies, caterpillars,
and beetle larvae. Top and bottom: Geocoris species
John Davidson
Pirate Bugs
Order Hemiptera
Family Miridae
John Davidson
Life History: Most mirids
feed on plants, but some
are predaceous.
Prey: Mites and plantfeeding insects; lace bugs,
cotton aphid, tobacco
budworm.
David Laughlin
Top: Deraeocoris nebulosus adult
Bottom: Pirate bug adult (L) and nymph (R)
Stink Bugs
Order Hemiptera
Family Pentatomidae
Life History: Most feed
on plants, but some
are predaceous. Many
discharge a distasteful
smell when handled.
Whitney Cranshaw
Predatory stink bug feeding
on elm leaf beetle larva
Prey: Caterpillars and beetles such as
Colorado potato beetle and Mexican bean
beetle.
Stink Bugs
David Laughlin
CW from top left: Podisus
maculiventris adult attacking
tussock moth caterpillar,
Perillus bioculatus nymph
feeding on beetle larva, P.
bioculatus nymph feeding on
hornworm
Whitney Cranshaw
John Davidson
Assassin Bugs
Order Hemiptera
Family Reduviidae
Life History: Assassin
bugs feed by piercing
prey with their beaks to
suck out juices.
Prey: Caterpillars, small
flying insects, aphids,
and leafhoppers.
Wheel bug (Arilus cristatus)
Aphelinid Wasps
Order Hymenoptera
Family Aphelinidae
Life History: Solitary,
lay eggs in or outside
hosts. Females
usually reproduce
parthenogenetically,
males are rare.
John Davidson
Encarsia formosa adult
Prey: Aphids, mealybugs, psyllids, scales, and
whiteflies.
Braconid Wasps
Order Hymenoptera
Family Braconidae
Life History: Life
cycle is 10–14 days.
Larvae are internal
parasitoids; many
pupate outside hosts. More females than males.
John Davidson
Prey: Aphids, larvae of beetles, flies, sawflies,
and caterpillars; tomato hornworm, imported
cabbageworm, gypsy moth.
Chalcid Wasps
Order Hymenoptera
Family Chalcidae
Life History: Larvae
are internal parasitoids
of other insects.
John Davidson
Prey: Moths,
butterflies, beetles,
flies, other wasps.
David Laughlin
Encyrtid Wasps
Order Hymenoptera
Family Encyrtidae
John Davidson
Life History: Larvae
are parasitoids;
adults live 2–3 days.
Prey: Ticks, insect
eggs, larvae, and
pupae; beetles,
bugs, moths,
mealybugs, scales.
John Davidson
Top: Encyrtus fuscus reared from
hemispherical scale
Bottom: Parasitized hemispherical
scales turned black
Ichneumonid Wasps
Order Hymenoptera
Family Ichneumonidae
Life History: Larvae are
internal or external
parasitoids.
Whitney Cranshaw
Prey species: Larvae and pupae of beetles,
wasps, and caterpillars; armyworms,
cabbage looper, fall webworm, oakworms,
tent caterpillars, tussock moths, European
corn borer.
Scelionid Wasps
Order Hymenoptera
Family Scelionidae
Life History:
Larvae are internal
parasitoids of other
insects and spiders.
Prey: Insect and spider eggs, especially
those of true bugs and moths.
John Davidson
Trichogramma Wasps
Order Hymenoptera
Family
Trichogrammatidae
University of California at Berkeley
Life History: Larvae
are internal parasitoids
of other insects.
Prey: Sawfly and moth eggs; cabbageworm,
tomato hornworm, corn earworm, codling
moth, cutworm, armyworm, cabbage looper,
European corn borer, tomato fruitworm.
Vespid Wasps
Order Hymenoptera
Family Vespidae
Life History: Many have
annual colonies with
queens, workers, and
males.
John Davidson
Yellowjacket with caterpillar
Prey: Caterpillars and other
insects. May bother people
at picnics.
Paper wasp (Polistes species)
Ants
Order Hymenoptera
Family Formicidae
Life History: Annual colonies with queens,
workers, and drones (males).
Prey: Other
arthropods, as
well as pollen,
nectar, and
human food.
Workers with eggs
Jim Occi, BugPics, www.insectimages.org
Ants
Clemson University, USDA Cooperative Extension Slide
Series, www.forestryimages.org
Above: Carpenter ant
(Camponotus sp.)
Right: Red imported fire
ants (Solenopsis invicta)
with cerambycid larvae
Herbert A. "Joe" Pase III, Texas Forest Service, www.insectimages.org
Green Lacewings
Order Neuroptera
Family Chrysopidae
Life History: Oval,
white eggs laid
singly on stalks 8 mm long. Small gray larvae
spin cocoons and pupate on undersides of
leaves when they are 10 mm long. One to ten
generations per year.
Prey: Larvae feed on aphids and other small
insects. Adults feed on honeydew and pollen.
Brown Lacewings
Order Neuroptera
Family Hemerobiidae
John Davidson
Life History: Oval,
white eggs laid singly.
Small gray larvae spin
cocoons and pupate on undersides of leaves
when they are 10 mm long. One to ten
generations per year.
Prey: Mites, aphids, mealybugs, scales,
whiteflies, and other soft-bodied arthropods.
Mantidflies
Order Neuroptera
Family Mantispidae
David Laughlin
Life History: Nocturnal
insects that resemble
mantids. Both larvae
and adults are predaceous.
Prey: Spider egg sacs, bee and wasp larvae.
Predatory Thrips
Order Thysanoptera
Families Aleolothripidae
and Phlaeothripidae
Life History: Sexual or
asexual reproduction.
Nymphs resemble adults in size and color.
Several generations per year.
John Davidson
Prey: Pest thrips, aphids, mites, whiteflies,
and other soft-bodied insects.
Centipedes
Class Chilopoda
Life History: Nocturnal; in
gardens and houses.
Prey: Small arthropods.
Tree of Life
http://tolweb.org/tree/phylogeny.html
Tree of Life
http://tolweb.org/tree/phylogeny.html
Left: Lithobius forficatu
Above: House centipede
(Scutigera coleoptrata)