1. ARTHROPODS
AND
ECHINODERMS
ABCS
101
Department
of
Animal
Biology
and
ConservaBon
Science
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
1

2. Purpose
This
aspect
of
the
course
is
to
assist
students
to
recognize
the
basic
structure
and
funcEon
of
arthropods
and
echinoderms
as
well
as
their
basic
ecology;
the
applicaEon
of
this
knowledge
should
aid
in
the
management
of
biodiversity
towards
improving
the
student’s
quality
of
life
and
that
of
the
larger
community.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
2

3. ObjecBves
• IdenEfy
features
and
characters
for
classificaEon
into
groups
(taxonomic
nomenclature)
• Describe
the
biology
of
arthropods
and
echinoderms
in
their
varied
environments
• Demonstrate
the
importance
of
arthropods
and
echinoderms
to
life
• Apply
knowledge
gained
of
arthropods
and
echinoderms
to
help
develop
biodiversity
conservaEon
strategies
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
3

4. Principal
learning
outcome
By
the
end
of
this
part
of
the
course,
students
should
be
able
to
use
the
knowledge
acquired
to
correctly
idenEfy
some
common
groups
of
arthropods
and
echinoderms,
describe
how
they
are
generally
adapted
to
their
environments
and
aid
in
management
and
maintenance
of
biodiversity
efforts
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
4

5. Procedure
•
•
•
•
•
•
•
Lectures
Group
discussions
Audio
visual
aids
Assignments
PracEcals
Interim
assessments
ExaminaEons
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
5

6. Scope
WEEK 1
Arthropoda: Chelicerata, Merostomata, Arachnida
and Mandibulata,
WEEK 2
Arthopoda: Diplopoda, Chilopoda, Crustacea and Hexapoda
(Insecta)
WEEK 3
Echinodermata: Echiroidea, Asteroidea, Ophiuroidea,
Crinoidea, Holothuroidea, the water vascular system
WEEK 4
AMMENDMENTS?
Reading
Materials:
• Life
The
Science
of
Biology:
Purves,
Sadava,
Orians
and
Heller
(2008).
8th
Ed.
Sinauer
Associates,
Inc./
W.H.
Freema
and
Company
• Zoology:
Miller
and
Harley
(1996).
3rd
Ed.
WCB/McGraw
Hill.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
6

7. ARTHROPODS
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
7

8. ObjecBves
• Describe
the
general
morphology
of
arthropods
• IdenEfy
and
classify
arthropods
into
groups
based
on
unique
characterisEcs
• Describe
the
distribuEon
and
coping
mechanisms
to
problems
of
life
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
8

9. ARTHROPODS
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
9

10. ARTHROPODS
• What
account
for
their
success?
– Metamerism
and
TagmaEzaEon
– Exoskeleton
– Metamorphosis
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
10

11. ARTHROPOD
CHARACTERISTICS
• Main
features:
– segmented
body
(metamerism),
-­‐jointed
appendages,
-­‐
hard
external
skeleton
(ChiEnous
exoskeleton).
– Body
segmentaEon
and
tagmaEzaEon
• Three
disEnct
body
segments
– Head,
Thorax
and
Abdomen.
• Head
may
fuse
with
thorax:
Cephalothorax
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
11

12. ARTHROPOD
CHARACTERISTICS
• Jointed
appendages:
-­‐Structures
extending
from
body
wall
• Bending
joints
[“Arthro”
“poda”
means
“joint”
“footed”]
• Movement
• Exoskeleton:
-­‐Rigid
outer
layer
composed
primarily
of
chiEn.
• ProtecEon
against
predators
and
water
loss
• Structural
support
and
muscle
ajachment
for
movement
• Adult
grow
by
ecdysis;
periodic
shedding
of
exoskeleton
for
a
new
larger
one
(molEng).
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
12

13. ARTHROPOD
CHARACTERISTICS
ChiBnous
exoskeleton
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
13

14. ARTHROPOD
CHARACTERISTICS
RespiraBon
and
circulaBon
• Majority
breathe
through
network
of
fine
tubes:
trachea
• Others
breathe
through
book
lungs.
• Most
aquaEc
arthropods
breathe
through
gills.
• Open
circulatory
system:
blood
is
not
always
contained
within
vessels.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
14

15. ARTHROPOD
CHARACTERISTICS
Feeding,
digesBon
and
excreBon
• Varied
mouthparts
and
appendages
for
obtaining
food
• IntesEnal
tract
extends
from
mouth
to
anus
– contains
structures
specialized
for:
storage,
mechanical
and
chemical
digesEon,
nutrient
absorpEon,
and
eliminaEon
of
digesEve
wastes
• Excretory
system
composed
of
Malpighian
tubules.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
15

16. ARTHROPOD
CHARACTERISTICS
Feeding,
digesBon
and
excreBon
• Varied
mouth
part
types
– BiEng
and
chewing
– Piecing
and
sucking
– Sucking
– Tearing
and
sucking
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
16

17. ARTHROPOD
CHARACTERISTICS
Vision:
Compound
eyes
• Predominantly compound eyes,
composed of thousands of individual
visual units.
• Units send signals to brain which then
composes image of object.
• Compound eye exceptionally good for
movement detection
– Hence difficult to sneak up on flies
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
17

18. ARTHROPOD
CHARACTERISTICS
ReproducBon
• Reproduce
via
sexual
reproducEon
– Internal
ferElizaEon
in
most
species,
but
external
in
some
• Most
species
are
dioecious
(i.e.
have
separate
sexes)
• Sedentary/parasiEc
arthropods
species
are
olen
hermaphodites
– Free-­‐living
species
may
exhibit
various
degrees
of
sexual
reproducEon.
– Parthenogenesis
commonly
occurs
in
Insects,
Branchiopods
and
some
freshwater
copepods
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
18

19. ARTHROPOD
LIFE
CYCLE
• Arthropods
mostly
reproduce
only
sexually,
– parthenogenesis
may
occur
• Eggs
laid
outside
female’s
body
• No
parental
care
received.
ExcepEon
are
scorpions
Metamorphosis
– Complete
metamorphosis
– Incomplete
metamorphosis
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
19

20. ARTHROPOD
LIFE
CYCLE
MolBng
• Exoskeleton
for
protecEon
but
does
not
grow,
periodic
shedding
of
exoskeleton
required
and
grow
a
new
one.
•
The
process
of
shedding
and
discarding
exoskeleton
termed;
mol6ng
via
ecdysis
•
Allows
arthropods
to
grow
a
larger
body
•
Most
arthropods
molt
several
Emes
before
adulthood
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
20

21. ARTHROPOD
DIVERSITY
• Total
number
of
arthropods
exceeds
number
of
all
other
animal
species
combined
• Due
to
their
enormous
evoluEonary
success
• Exoskeleton
provides
adaptaEon
to
life
on
land/
water;
small
sized,
and
show
a
wide
range
of
specializaEon
in
food
sources
and
habitats.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
21

22. ARTHROPOD
DIVERSITY
There
are
4
main
Arthropods
groups
(Subphyllum):
• Uniramia
(Hexapoda
(insects),
Myriapoda
(millipedes
and
cenEpedes))
• Crustacea
(lobsters
and
shrimps),
• Chelicerata
(spiders,
scorpions,
mites,
Ecks,
and
horseshoe
crabs)
• Trilobita
(exEnct
lived
during
the
Cambrian
period
-­‐
600
million
yrs
ago.)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
22

23. ARTHROPOD
DIVERSITY
•
Living
arthropods
are
tradiEonally
divided
into
two
groups—
arthropods
that
have
jaws
and
arthropods
that
have
fangs
or
pincers.
• Members
of
the
subphylum
Chelicerata
have
fangs
or
pincers.
• Members
of
the
other
subphyla
have
jaws-­‐
Mandibulata
(Mandibulata
is
a
group
of
arthropods
characterized
by
mandibles
(mouthparts)
used
for
biEng,
cupng,
and
holding
food)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
23

24. PHYLLUM
ARTHROPODA
•
•
•
•
Diplopoda
Myriapoda
Chilopoda
Insecta
(Hexapoda)
Crustacea
November
9,
2012
MANDIBULATA
ABCS
101
(Introductory
Animal
Biology)
24

25. PHYLUM
ARTHROPODA
 Subphylum
Uniramia
Class
Chilopoda
Class
Diplopoda
Class
Insecta/Hexapoda
(Unbranched
(uniramous)
appendages
with
a
single
pair
of
antennae)

Subphylum
Crustacea
Class
Malacostraca
Class
Remipedia
Class
Copepoda
Class
Cirripedia
Class
Cephalocarida
Class
Branchiopoda
(Biramous
appendages:
branched
appendage
with
2
pairs
of
antennae)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
25

26. CHILOPODA
AND
DIPLOPODA
(CENTIPEDES
AND
MILLIPEDES)
Myriapods
•
The
name
Myriapoda
mean
“many
footed.”
•
Each
myriapod
has
a
head
region
that
is
followed
by
many
similar
segments
•
CenEpedes
have
one
pair
of
legs
per
segment
and
millipedes
usually
have
two
pair
of
legs
per
segment
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
26

27. CLASS
CHILOPODA
• Class
of
terrestrial
Myriapods
comprising
approximately
3000
species
• distributed
over
all
conEnents,
from
sea
level
to
high
alEtudes
• Some
species
are
however
marine
• CenEpedes
are
nocturnal
predators
that
live
under
stones,
under
the
bark
of
tree
trunks,
in
moss,
in
leaf
lijer,
soil,
under
logs,
in
caves
and
occassionally
in
people’s
home.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
27

28. CLASS
CHILOPODA
• Legs
are
long,
enabling
them
to
run
rapidly
• Predominantly
sol-­‐bodied
myriapods,
measuring
1-­‐10
cm
long,
bear
15-­‐191
pairs
of
legs
(Minelli
1993)
• Posses
a
head
and
elongated
trunk
with
many
segments,
each
bearing
a
legs
• Body
is
covered
by
unwaxed
cuEcle
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
28

29. Class
Chilopoda
•
Head
bears
a
single
pair
of
antennae
a
pair
of
mandibles
for
chewing
a
pair
of
first
and
second
maxillae
a
pair
of
maxillipeds
(modified
for
subduing
prey)
contain
poison
glands
and
resemble
fangs
•
Presence
of
large
brain
connected
with
a
ventral
chain
of
ganglia
•
lacks
eyes
(when
present,
are
generally
simple
light
receptors
called
ocelli
)
Compound
eyes
occur
in
one
family,
and
simple
eyes
or
none
at
all
in
many
The
feelers,
certain
bristles,
and
porEons
of
the
skin
are
also
sensory.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
29

30. Class
Chilopoda
 Head
is
followed
by
15
or
more
leg-­‐
bearing
segements.
Some
species
have
repugnatorial
glands
on
the
ventral
surface
of
each
segement
or
on
some
of
the
legs
themselves
(these
gland
discourage
predaEon
by
producing
an
adhesive
ejaculate)
 A
number
of
sp.
produce
silk
from
silk
glands.
Most
species
are
long-­‐legged
runners,
some
have
legs
adapted
for
burrowing
through
the
soil
(in
these
sp.
,
legs
are
reduced
and
thrust
is
generated
by
exploiEng
the
properEes
of
hydrostaEc
skeleton
–
earthworm
like)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
30

31. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
31

32. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
32

33. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
33

34. Class
Chilopoda
Feeding
•
They
are
carnivorous
and
feed
upon
other
animals
mostly
insects
some
larger
ones
cenEpedes
have
been
known
to
feed
on
snakes
mice
and
frogs
•
Aler
using
their
jaws
to
capture
their
prey,
they
inject
a
venom
into
the
animal
to
kill
it.
•
Prey
is
captured
and
killed
with
poison
claws
located
just
behind
the
head
on
the
first
trunk
segment.
•
Pair
of
poison
glands
at
the
base
of
the
claws
empty
into
ducts
that
open
at
the
Ep
of
the
pointed
fanglike
claw.
The
alimentary
canal
is
straight,
food
is
digested
and
absorbed
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
34

35. Class
Chilopoda
CirculaEon
and
Gaseous
exchange

The
heart
is
a
chambered
dorsal
vessel
 RespiraEon
is
accomplished
by
trachea,
but
spiracles
cannot
be
closed.
(thus
most
are
restricted
to
moist
environments
due
to
difficulty
in
restricEng
water
loss)
 Tracheae,
or
air
tubes,
open
on
the
sides
of
the
body
and
are
connected
to
one
another
on
each
side
Many
thus
conserve
water
by
nocturnal-­‐
that
is
by
avoiding
the
heat
of
the
day
and
becoming
acEve
only
at
night.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
35

36. CLASS
CHILOPODA
REPRODUCTION
and
GROWTH
• One
genus
bears
live
young;
the
others
lay
eggs
• FerElizaEon
is
internal
• ReproducEon
may
involve
courtship
display,
where
the
male
lays
down
silk
web.
• A
spermatophore
is
placed
in
the
web
and
picked
up
by
females
them
introduces
it
her
genital
opening
• Eggs
are
ferElized
as
they
are
laid.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
36

37. CLASS
CHILOPODA
REPRODUCTION
and
GROWTH
•
Some
cenEpedes
can
live
as
long
as
five
or
six
years.
• They
lay
their
eggs
in
the
soil
during
warmer
seasons.
• While
some
species
of
cenEpedes
can
add
segments
and
legs
as
they
mature,
others
are
born
with
their
complete
set
of
body
segments
and
legs.
• Most
cenEpedes
measure
about
2.5
to
5
cm
(about
1
to
2
in)
in
length,
but
some
tropical
species
grow
to
about
30
cm
(about
12
in)
through
molEng
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
37

38. CLASS
CHILOPODA
ExcreEon
The
major
excretory
structure
in
the
chilopoda
are
the
Malpighian
tubules
Some
uric
acid
is
produced,
but
major
waste
product
of
the
cenEpede
is
amonnia
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
38

39. CLASS
CHILOPODA
DIVERSITY
• A
total
of
five
orders
of
cenEpedes
are
currently
recognized
within
the
extant
Chilopoda:
• ScuEgeromorpha
• Lithobiomorpha
• CraterosEgmomorpha
• Scolo-­‐
pendromorpha
• Geophilomorpha.
• One
exEnct
order,
Devonobiomorpha,
is
also
accepted
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
39

40. CLASS
CHILOPODA
DIVERSITY
ScuEgeromorpha
(i.e.
the
synanthropic
cosmopolitan
house
cenEpede
ScuEgera
coleoptrata),
have
pseudo
faceted
eyes
resembling
the
compound
eyes
of
insects,
15
pairs
of
very
elongated
legs,
and
dorsal
respiratory
openings
There
are
also
15
pairs
of
legs
in
Lithobiomorpha
and
CraterosEgmomorpha,
a
poorly
known
group
comprising
two
species
from
New
Zealand
and
Tasmania.
The
Geophilomorpha
comprises
11
families
of
worm-­‐like
bodied
cenEpedes,
bearing
29-­‐191
pairs
of
short
legs.
The
largest
cenEpedes
(reaching
25
cm
long)
belong
to
the
Scolopendromorpha,
and
bear
21-­‐23
pairs
of
legs.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
40

41. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
41

42. 
The
bite
of
some
Scolopendromorpha
can
inflict
serious
injury
to
humans.

ScuEgeromorpha
and
Lithobiomorpha
have
a
type
of
development
known
as
anamorphic,
in
which
segment
number
increases
during
postembryonic
life
(Anamorpha).

Contrast,
Scolopendromorpha
and
Geophilomorpha
have
an
epimorphic
development,
in
which
the
definiEve
number
of
body
segments
appears
upon
hatching
(Epimorpha).

The
condiEon
of
Cratero-­‐sEgmomorpha
is
unclear
because
they
are
not
strictly
anamorphic,
as
they
achieve
the
final
number
of
legs
aler
only
one
molt,
and
have
been
suggested
to
be
the
sister
group
of
the
Epimorpha
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
42

43. CLASS
CHILOPODA
•
Some
species
of
cenEpedes
are
considered
venomous
to
humans,
but
their
bite
is
not
sufficiently
toxic
to
be
lethal
to
children
or
adults.
• A
bite
from
any
of
the
smaller
species
usually
produces
a
moderate
reacEon
that,
at
worst,
is
similar
to
a
bee
sEng.
• The
bite
of
the
larger
species
may
produce
local
inflammaEon,
redness,
and
swelling
–
and
occasionally
systemic
symptoms
that
disappear
in
four
to
five
hours.
•
Contrary
to
myth,
a
cenEpede
walking
on
your
skin
will
not
kill
the
Essue
or
cause
the
skin
to
rot.
•
• They
do,
however,
have
relaEvely
sharp
claws
on
their
legs
that
can
scratch.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
43

44. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
44

45. CLASS
DIPLOPODA
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
45

46. Class
Diplopoda
• Known
as
millipedes
(thousand-­‐
legged)
They
are
commonly
called
“thousand
leggers,”
even
though
they
may
only
have
60
to
400
legs.
• Abt
12,000
known
species,
abt
4X
the
number
of
known
cenEpede
sp.
• Primarily
slow
moving
deposit
feeders
that
plow
through
the
soil
and
decaying
organic
materials
(herbivorous)
• Some
carnivorous
sp.
occur
• Pairs
of
segments
have
become
fused
(
diplosegements
–
double
trunk
segments-­‐
resulEng
from
the
fusion
of
2
origInal
segment)
• Each
double
segment
has
two
pairs
of
legs
and
contain
2
pairs
of
spiracles
and
ventral
ganglia
• The
most
anterior
3
or
4
segments
have
only
a
single
pair
of
legs
• The
body
of
a
millipede
is
cylindrical
• In
many
sp.
the
integument
(body
covering)
is
impregnated
with
calcium
salts
(as
in
crustaceans)
making
their
covering
more
protecEve
against
abrasion
and
predaEon
than
that
of
the
cenEpede
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
46

47. Class
Diplopoda
 As
in
the
cenEpedes,
however,
the
cuEcle
is
not
waxy
 Many
sp.
lack
eyes,
but
as
many
as
80
ocelli
are
found
on
the
head
of
some
species

Compound
eyes
are
absent
 Head
appendages
consist
of
pair
of
mandibles
and
a
pair
of
maxillae
(DisEnct
second
maxillae
are
lacking
among
millipedes)
Instead
first
and
second
maxillae
on
each
side
are
fused
to
form
a
single
appendage
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
47

48. Class
Diplopoda
• Millipedes
consEtute
a
major
component
of
the
soil-­‐
lijer
macrofauna
• Some
species
(e.g.
Dendrostreptus
macracanthus,
Cleidogona
scandens)
occur
in
the
forest
canopy
and
have
been
found
in
epiphytes
such
as
bromeliads
• In
tropical
rain
forest
environments,
some
species
can
be
found
as
deep
as
20
cm
in
the
soil
• Millipedes
are
olen
collected
in
ropng
logs
and
under
stones,
as
well
as
in
ant
nests
as
potenEal
commensals
• Even
though
they
may
invade
houses,
they
pose
no
threat.
• They
do
not
bite,
sEng,
cause
structural
damage,
contaminate
foodstuffs,
or
eat
fiber
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
48

49. Class
Diplopoda
LocomoBon
and
protecBon
• Because
of
their
numerous
legs,
the
animals
walk
slowly,
with
a
wavelike
moEon
of
the
legs
down
the
body.
Their
legs
move
simultaneously
pushing
against
the
substrate,
thus
enabling
them
move
freely
in
their
habitat.
• In
length
they
range
from
about
0.2
to
23
cm
(about
0.1
to
9
in)
• In
most
species
there
is
the
sEnk
glands
with
secreEons
that
repel
or
kill
insect
predators.
• Most
sp
have
an
abundance
of
repugnatorial
glands
which
eject
a
variety
of
toxic,
repellent
secreEons
(hydrogen
cyanide
–
precursor
compound
+
enzyme
)
• Another
protecEve
strategy
is
to
curl
into
a
spiral
or
a
ball
when
threatened
• Millipedes
are
also
ajracted
to
lights,
and
it
is
common
to
have
them
migrate
to
lighted
areas.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
49

50. Class
Diplopoda
Feeding
• They
are
herbivorous
• The
principal
mouth
structures
are
the
mandibles
modified
for
scraping
and
chewing
• A
few
sp.
have
modified
mouth
parts
for
sucking
plant
juice
• The
animals
live
in
dark,
damp
places
and
feed
on
decaying
plant
life,
someEmes
damaging
crops
but
also
enriching
the
soil
• Most
millipedes
feed
on
damp
and
decaying
vegetaEon
and
leaf
lijer,
although
some
species
will
ajack
the
roots
and
lower
leaves
of
living
plants.
• They
spend
most
of
their
life
in
the
soil.
•
Adult
millipedes
spend
cooler
days
in
soil,
debris,
and
leaf
lijer
found
under
trees.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
50

51. Class
Diplopoda
DigesEon
• A
peritrophic
membrane
lines
the
midgut
of
millipedes,
presumably
to
protect
against
abrasion
• Food
becomesenclosed
by
this
membrane
as
it
moves
through
the
gut,
and
new
peri-­‐
trophic
membrane
is
secreted.
• Gut
is
esenEally
a
linear
tube.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
51

52. Class
Diplopoda
ReproducBon
and
Growth
• Sexual
• Usually
have
a
complex
male
copulatory
devices
that
are
modified
appendages.
• In
some
subclass
(Pentazonia),
the
last
two
or
three
pairs
of
legs
at
the
posterior
body
end
are
transformed
into
telopods,
which
are
used
by
the
males
during
copula
to
clasp
the
female
vulva.
• In
millipede
males
of
the
subclass
Helminthomorpha,
the
copulatory
organs
are
situated
at
the
7th
and
8th
body
rings,
replacing
one
or
two
pairs
of
walking
appendages
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
52

53. Class
Diplopoda
ReproducBon
and
Growth
• Sexual
reproducEon
• Sperms
are
transferred
to
the
female
with
modified
trunk
appendages
of
the
male,
called
gonods,
or
spermatophores.
• Eggs
are
ferElized
as
they
are
laid
• Female
millipedes
lay
their
eggs
usually
during
the
moist
seasons.
•
It
has
been
reported
that
a
female
millipede
can
produce
as
many
as
300
eggs
at
one
Eme.
• These
eggs
are
laid
in
the
soil
in
several
small
clusters
of
20
to
100
eggs.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
53

54. Class
Diplopoda
ReproducBon
and
Growth
• In
about
three
weeks,
the
eggs
hatch
into
Eny
larvae
with
only
three
pairs
of
legs.
•
As
millipedes
grow,
they
molt
from
seven
to
ten
Emes,
adding
addiEonal
body
segments
and
legs
with
each
molt.
• Millipedes
stop
growing
when
they
reach
sexual
maturity.
• Adults
may
live
for
two
to
five
years.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
54

55. Class
Diplopoda
• RespiraBon
and
CirculaBon
 The
heart
is
a
chambered
dorsal
vessel
 RespiraEon
is
accomplished
by
trachea,
but
spiracles
cannot
be
closed.(thus
most
are
restricted
to
moist
environments
due
to
difficulty
in
restricEng
water
loss)
 Tracheae,
or
air
tubes,
open
on
the
sides
of
the
body
and
are
connected
to
one
another
on
each
side
– Many
thus
conserve
water
by
nocturnal-­‐
that
is
by
avoiding
the
heat
of
the
day
and
becoming
acEve
only
at
night.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
55

56. Class
Diplopoda
Diversity
• The
144
currently
recognized
families
of
millipedes
are
classified
in
15
orders,which
are
arranged
in
three
subclasses:
» Penicillata,
» Pentazonia,
and
» Helminthomorpha.
• The
Penicillata,or
bristle
millipedes,
are
very
small
soil
dwellers
with
uncalcified
cuEcle.
The
group
contains
about
80
nominal
species
•
The
Pentazonia
(comprising
three
orders,
Glomeridesmida,
Glomerida,
and
Sphaerotheriida)
and
• the
Helminthomorpha
possess
a
strongly
calcified
cuEcle.
The
vast
majority
of
millipede
species
belongs
to
the
Helminthomorpha.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
56

57. Class
Diplopoda
and
Chilopoda
Millipedes
differ
from
cenEpedes
in
that
they
have
one
pair
of
short
antennae
on
the
head
and
two
pairs
of
legs
on
each
body
segment
Each
myriapod
has
a
head
region
that
is
followed
by
many
similar
segments.
CenBpedes
have
one
pair
of
legs
per
segment
and
millipedes
usually
have
two
pair
of
legs
per
segment.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
57

58. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
58

59. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
59

60. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
60

61. INTRODUCTORY
ANIMALS
BIOLOGY
ARTHROPODA
Cont’d
INSECTS
AND
CRUSTACEANS
Ms.
Juliet
Ewool
Dept.
of
Animal
Biology
&
ConservaBon
Science
(DABCS)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
61

62. PHYLUM
ARTHROPODA
 Subphylum
Uniramia
Class
Chilopoda
Class
Diplopoda
Class
Insecta
(They
possess
unbranched
(uniramous)
appendages
and
Bear
a
single
pair
of
antennae)

Subphylum
Crustacea
Class
Malascostraca
Class
Ostracoda
Class
Copepoda
Class
Cirripedia
Class
Pentastomida
(Biramous
appendages:
branched
appendage
with
2
pairs
of
antennae)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
62

63. Subphylum
Uniramia
• Class
Chilopoda
• Class
Diplopoda
• Class
Insecta
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
63

64. Subphylum
Uniramia
Class
Insecta
• Over
750,000
described
species
(most
successful
group
of
animals
on
our
planet
in
terms
of
diversity
and
number
of
species,
as
well
as
number
of
individuals
• Among
the
best
studied
of
the
invertebrates,
in
a
large
part
due
to
their
omnipresent
impact
on
humans
– Pollinate
most
flowering
plant
of
Agric
importance
as
well
as
transmits
various
diseases
to
man
• Mostly
terrestrial
sp.
– May
live
as
adults
on
land
and
have
aquaEc
larvae
• If
aquaEc,
then
fresh
water,
few
are
truly
marine
and
others
inhabit
the
shore
between
the
Edes/saltwater
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
64
mashes

65. Subphylum
Uniramia
Class
Insecta
• INSECT
CHARACTERISTICS
• Most
insects
share
– the
same
general
body
plan
• head,
thorax
and
abdomen
– specialized
mouthparts
for
feeding,
– a
unique
life
cycle,
and
–
the
ability
to
fly
– Most
insects
have
mouthparts
for
eaEng
called
mandibles.
• These
specialized
c(Introductory
Animal
Biology)
mouth
parts
are
omplex
set
of
ABCS
101
adapted
for
chewing,
sucking,
or
lapping
November
9,
2012
65

66. Subphylum
Uniramia
Class
Insecta
• In
insects,
the
thorax
is
composed
of
three
fused
segments
(3
disEnct
tagma)
-­‐
A
flexible
joint
separaEng
the
head
and
thorax
– Three
pairs
of
jointed
walking
legs
(hexapods),
emerging
from
and
ajached
to
the
thorax
directed
ventrally
– Usually
two
pairs
of
antennae
of
wings
carried
dorsally
on
the
thorax
• Wings
are
out
folding
of
the
thoracic
integument
and
consist
of
two
thin
chiEnuous
sheets.
• One
pair
of
antennae
protrudes
from
the
head,
and
the
sense
organs
include
both
simple
and
compound
eyes
– The
main
light
receptors
are
the
pair
of
compound
eyes,
but
single-­‐
unit
eyes
(ocelli)are
usually
present
on
the
head
as
well
• Abdomen
lacks
appendages,
except
for
a
pair
of
sensory
cerci
borne
on
the
last
abdominal
segment
• November
9,
2012
Communicate
with
each
o01
(Introductory
Adances”
and
by
chemical
ABCS
1 ther
by
“ nimal
Biology)
called
pheromones.
66

67. Subphylum
Uniramia
Class
Insecta
• May
be
described
as
an
arEculated,
tracheated,
hexapod.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
67

68. Subphylum
Uniramia
Class
Insecta
• Legs
may
be
modified
for
walking,
jumping,
swimming,
digging
or
grasping,
and
are
generally
studded
with
a
variety
of
sensory
receptors,
including
receptors
for
taste,
smell
and
touch
•
such
receptors
are
also
found
on
the
mouthparts
and
elsewhere
on
the
body
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
68

69. Subphylum
Uniramia
Class
Insecta
• Head
bears
four
pairs
of
appendages;
– one
pair
of
uniramous
antennae
– Three
pairs
of
mouth
parts
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
69

70. Subphylum
Uniramia
Class
Insecta
In
sequence,
the
mouthparts
are
the
mandibles,
the
maxillae,
and
a
pair
of
second
maxillae
that
are
fused
to
form
a
single
appendage
called
the
Labium.
The
mandiles
are
sheilded
anteriorly
by
a
downwards
extension
of
the
head
called
the
labrum.
(Introductory
Animal
Biology)
November
9,
2012
ABCS
101
70

71. Subphylum
Uniramia
Class
Insecta
• Morphology
of
these
mouthparts
varies
considerably
according
to
the
insect’s
feeding
biology
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
71

72. Subphylum
Uniramia
Class
Insecta
LocomoBon
• Movement
in
insects
depends,
as
it
does
in
vertebrates,
on
muscles
contracEng
and
pulling
on
jointed
limbs
or
other
appendages.
• The
muscles
are
within
the
body
and
limbs,
however,
and
are
ajached
to
the
inside
of
the
cuEcle.
• A
pair
of
antagonisEc
muscles
is
ajached
across
a
joint
in
a
way
which
could
bend
and
straighten
the
limb.
• Many
of
the
joints
in
the
-­‐insect
are
of
the
"peg
and
socket"
type.
• They
permit
movement
in
one
plane
only,
like
a
hinge
joint,
but
since
there
are
several
such
joints
in
a
limb,
each
operaEng
in
a
different
direcEon,
the
limb
as
a
whole
can
describe
fairly
free
direcEonal
movement.
• Insects
move
by
walking,
jumping,
running,
swimming
etc.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
72

73. Subphylum
Uniramia
Class
Insecta
Walking
• The
characterisEc
walking
pajern
of
an
insect
involves
moving
three
legs
at
a
Eme.
The
body
is
supported
by
a
"tripod"
of
three
legs
while
the
other
three
are
swinging
forward
to
a
new
posiEon.
• On
the
last
tarsal
joint
are
claws
and,
depending
on
the
species,
adhesive
pads
which
enable
the
insect
to
climb
very
smooth
surfaces.
• The
precise
mechanism
of
adhesion
is
uncertain.
• ModificaEon
of
the
limbs
and
their
musculature
enables
insects
to
leap,
e.g.
grasshopper,
or
swim,
e.g.
water
beetles.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
73

74. Subphylum
Uniramia
Class
Insecta
Flying
• In
insects
with
relaEvely
light
bodies
and
large
wings
such
as
bujerflies
and
dragonflies,
the
wing
muscles
in
the
thorax
pull
directly
on
the
wing
where
it
is
arEculated
to
the
thorax,
levering
it
up
and
down.
•
Insects
such
as
bees,
wasps
and
flies,
with
compact
bodies
and
a
smaller
wing
area
have
indirect
flight
muscles
which
elevate
and
depress
the
wings
very
rapidly
by
pulling
on
the
walls
of
the
thorax
and
changing
its
shape.
• In
both
cases
there
are
direct
flight
muscles
which,
by
acEng
on
the
wing
inserEon,
can
alter
its
angle
in
the
air.
• During
the
down
stroke
the
wing
is
held
horizontally,
so
thrusEng
downwards
on
the
air
and
producing
a
liling
force.
• During
the
upstroke
the
wing
is
rotated
verEcally
and
offers
lijle
.
resistance
during
its
upward
movement
through
the
air
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
74

75. Subphylum
Uranimia
Class
Insecta
ADAPTATIONS
FOR
FLIGHT
• Insects
are
adapted
for
flight
by
having
a
lightweight
body,
wings,
and
strong
muscles
to
power
flight.
– Insects
were
the
first
animals
to
have
wings.
– Flight
was
a
great
evoluEonary
innovaEon.
Flying
insects
were
able
to
reach
previously
inaccessible
food
sources
and
to
escape
quickly
from
danger.
– An
insect’s
wings
develop
from
saclike
outgrowths
of
the
body
wall
of
the
thorax.
–
Most
insects
have
two
pairs
of
wings.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
75

76. Subphylum
Uniramia
Class
Insecta
Feeding
• Insects
feed
on
variety
of
nutriEve
sources,
including
plants
and
animal
Essues
and
on
fluids
• It
is
not
possible
to
make
very
useful
generalizaEons
about
the
feeding
methods
of
insects
• their
mouth
parts,
hinged
to
the
head
below
the
mouth,
extract
or
manipulate
food
in
one
way
or
another
– modified
and
adapted
to
exploit
different
kinds
of
food
source
•
•
The
basic
pajern
of
these
mouth
parts
is
the
same
in
most
insects
but
in
the
course
of
evoluEon
they
have
evolved.
The
least
modified
are
probably
those
of
insects
such
as
caterpillars,
grasshoppers,
locusts
and
cockroaches
in
which
the
first
pair
of
appendages,
mandibles,
form
sturdy
jaws,
working
sideways
across
the
mouth
and
cupng
off
pieces
of
vegetaEon
which
are
manipulated
into
the
mouth
by
the
other
mouth
parts,
the
maxillae
and
labium.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
76

77. Subphylum
Uniramia
Class
Insecta
• Aphids
for
eg.
feed
on
plant
juices
that
they
suck
from
leaves
and
stems.
Their
mouthparts
are
greatly
elongated
to
form
a
piercing
and
sucking
proboscis.
The
maxillae
fit
together
to
form
a
tube
which
can
be
pushed
into
plant
Essues
to
reach
the
food-­‐conducEng
vessels
of
the
phloem
and
so
extract
nutrients.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
Aphid
mouth
parts
are
elongated
and
modified
to
pierce
plant
Essue
to
suck
up
plant
juices.
77

78. Subphylum
Uniramia
Class
Insecta
• The
mosquito
has
mandibles
and
maxillae
in
the
form
of
slender,
sharp
stylets
which
can
cut
through
the
skin
of
a
mammal
as
well
as
penetraEng
plant
Essues.
• To
obtain
a
blood
meal
the
mosquito
inserts
its
mouth
parts
through
the
skin
to
reach
a
capillary
and
then
sucks
blood
through
a
tube
formed
from
the
labrum
or
"front
lip"
which
precedes
the
mouth
parts.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
78

79. Subphylum
Uniramia
Class
Insecta
Feeding
• Another
tubular
structure,
the
hypopharynx,
serves
to
inject
into
the
wound
a
substance
which
prevents
the
blood
from
clopng
and
so
blocking
the
tubular
labrum.
• In
both
aphid
and
mosquito
the
labium
is
rolled
round
the
other
mouth
parts,
enclosing
them
in
a
sheath
when
they
are
not
being
used.
• In
the
bujerfly,
only
the
maxillae
contribute
to
the
feeding
apparatus.
– The
maxillae
are
greatly
elongated
and
in
the
form
of
half
tubes,
i.e.
like
a
drinking
straw
split
down
its
length.
– They
can
be
fijed
together
to
form
a
tube
through
which
nectar
is
sucked
from
the
flowers.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
79

80. Subphylum
Uniramia
Class
Insecta
Feeding
• The
housefly
also
sucks
liquid
but
its
mouthparts
cannot
penetrate
Essue.
Instead
the
labium
is
enlarged
to
form
a
proboscis
which
terminates
in
two
pads
whose
surface
is
channelled
by
grooves
called
pseudotracheae.
• The
fly
applies
its
proboscis
to
the
food
and
pumps
saliva
along
the
channels
and
over
the
food.
• The
saliva
dissolves
soluble
parts
of
the
food
and
may
contain
enzymes
which
digest
some
of
the
insoluble
majer.
• The
nutrient
liquid
is
then
drawn
back
along
the
pseudotracheae
and
pumped
into
the
alimentary
canal.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
80

81. Subphylum
Uniramia
Class
Insecta
Feeding
• The
esophagus
is
highly
muscularized
and
serves
as
a
pump,
moving
food
into
a
crop
for
storage
and/or
preliminary
digesEon
• A
proventriculus
is
generally
present,
funcEoning
as
a
valve
to
regulate
the
passage
of
food
and
in
some
species
to
grind
ingested
food
• DigesEon
and
absorpEon
occur
in
the
mid
gut
and
it
associated
gastric
ceca
• The
walls
of
the
mid
gut
are
olen
lined
by
peritrophic
membrane,
as
in
the
Diplopods
(membrane
is
discarded
and
renewed
periodically).
• SymbioEc
bacteria
and
protozoans
harboured
in
the
gastric
ceca
of
many
species
parEcipate
in
the
digesEve
process
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
81

82.
Subphylum
Uniramia
Class
Insecta
(a) an
insect
(b)Sagijal
cross
secEon
through
a
formica
worker
showing
November
9,
2012
internal
anatomy
ABCS
101
(Introductory
Animal
Biology)
82

83. Subphylum
Uniramia
Class
Insecta
The
alimentary
canal
of
an
insect
Some
insects
may
house
receptors
that
monitor
the
degree
to
which
the
body
is
stretched
during
feeding
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
83

84. Subphylum
Uranimia
Class
Insecta
ExcreEon
• ExcreEon
is
accomplished
by
2
to
many
slender
Malpighian
tubules
which
receives
metabolic
wastes
from
the
blood
and
aler
concentraEng
them,
discharge
them
into
the
intesEnes
• Uric
acid
is
the
primary
end
product
of
protein
metabolism
among
insects;
this
non
toxic
nitrogenous
compound
is
excreted
in
nearly
dry
solid
forms.
• Several
mechanisms
are
involved
in
insect
waste
eliminaEon
• Many
insects
also
posses
nephrocytes
as
found
in
arachnids
• Before
waste
reaches
the
anus,
most
of
the
water
is
resorbed
from
the
fecal
material
by
the
rectal
glands
of
the
hindgut
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
84

85. Subphylum
Uranimia
Class
Insecta
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
85

86. ExcreBon
Subphylum
Uranimia
Class
Insecta
• Insects
eliminate
a
significant
fracEon
of
their
nitrogenous
wastes
as
water-­‐
insoluble
uric
acid
and
related
compounds
• Such
compounds
are
eliminated
from
the
body
in
nearly
dry
forms,
as
most
of
the
water
in
the
urine
is
resorbed
in
transit
through
the
rectum
• This
is
an
outstanding
physiological
adaptaEon
for
terrestrial
existence
• Waste
products,
notably
a
soluble
derivaEve
of
uric
acid,
are
acEvely
transported
from
the
blood
into
the
distal
porEon
of
the
malpighian
tubules
• Increased
acidity
in
the
proximal
porEon
of
the
tubules
causes
the
uric
acid
to
precipitate
out
of
soluEon
• Most
of
the
water
contained
in
the
urine
is
then
resorbed
during
its
passage
through
the
rectum
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
86

87. Subphylum
Uranimia
Class
Insecta
ExcreEon
The
major
excretory
organs
are
called
Malpighian
tubules
ABCS
101
(Introductory
Animal
Biology)
There
are
abt
250
pairs
found
in
insect
hemoceal
November
9,
2012
87

88. Subphylum
Uranimia
Class
Insecta
Gaseous
exchange
• One
pair
of
spiracles
opening
into
the
tracheal
system
is
found
on
the
thorax,
with
addiEonal
pairs
of
spiracles
located
on
many
of
the
abdominal
segments
• The
trachea
are
lined
by
a
cuEcle,
which
is
shed
and
resecreted
by
the
underlying
epidermia
each
Eme
the
insect
molts,
and
the
tubules
are
kept
from
collasping
by
means
of
chiEnuous
rings
embeded
in
the
walls
• The
trachae
Essue
branch
to
form
a
network
of
smaller
tubules
called
tracheoles;
which
are
less
then
1
um
in
diameter.
• These
branch
again
and
terminate
directly
on
the
insect’s
Essue.
Thus,
gas
is
exchanged
between
the
Essues
and
the
environment
without
the
involvement
of
the
blood
circulatory
system
• Some
insects
species
lack
trachea,
either
as
iology)
or
during
development
ABCS
101
(Introductory
Animal
B adults
88
November
9,
2012

89. Subphylum
Uranimia
Class
Insecta
Gaseous
exchange
Largely
terrestrial
thus
to
cope,
gas
exchange
have
been
internalized
by
means
of
tracheal
system
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
89

90. Subphylum
Uranimia
Class
Insecta
ReproducEon
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
90

91. Insect
CopulaBon
– •
All
insects
have
internal
ferElizaEon
– •
Most
insects
copulate
’normally’
• –
the
male
and
female
genitalia
engage
and
sperm
are
– transferred
to
site(s)
of
sperm
storage.
– •
Sperm
maybe
transferred
free
or
in
a
sperm
– package
-­‐
spermatophore
– •
Some
species
have
‘traumaEc’
inseminaEon
• –
paragenital
system
• –
e.g.
Cimicid
bugs
(bedbugs
–
Vägglöss)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
91

92. Subphylum
Uranimia
Class
Insecta
ReproducEon
and
development
Most insects reproduce sexually 101
(Introductory
Animal
Biology)
November
9,
2012
ABCS
92

93. Subphylum
Uranimia
Class
Insecta
Some reproduce asexually
– Parthenogenesis
– Aphids (Homoptera)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
93

94. Subphylum
Uranimia
Class
Insecta
Sexual
reproducBon
• Sexes
are
separate
and
ferElizaEon
is
internal
(several
molts
during
development)
INSECT
LIFE
CYCLE
•
Insect
development
is
unique
among
arthropods
• Insects
have
a
unique
life
cycle
compared
with
other
arthropods.
– During
development,
a
young
insect
undergoes
metamorphosis.
•
Metamorphosis
is
a
dramaBc
physical
change,
which
can
be
complete
or
incomplete.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
94

95. • Sexual
reproducEon
in
insects
–
Insect
lifecycles
-­‐
three
fundamentaltypes
1.
Ametabolous
–
no
metamorphosis
2.
Hemimetabolous
–
incomplete
metamorphosis
(no
pupal
stage)
There
are
several
developmental
stages
called
nymphal
stages
and
gradual
metamorphosis
(change
in
body
form)
to
the
adult
form
3.
Holometabolous
–
full
/
complete
metamorphosis
with
4
disEnct
stages
in
the
life
cycle;
Egg
–
Larva
–
pupa
–
adult
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
95

96. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
96

97. Subphylum
Uranimia
Class
Insecta
Incomplete
metamorphosis
•
•
•
November
9,
2012
A
smaller
number
of
insect
species
undergo
incomplete
metamorphosis.
–
During
incomplete
metamorphosis,
the
egg
hatches
into
a
juvenile,
or
nymph,
that
looks
like
a
small,
wingless
adult.
–
A]er
several
molts,
the
nymph
develops
into
a
sexually
mature
adult.
ABCS
101
(Introductory
Animal
Biology)
97

98. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
98

99. Subphylum
Uranimia
Class
Insecta
Complete
metamorphosis
• In
complete
metamorphosis,
the
wingless
larva
grows
in
size
and
passes
through
a
number
of
molts
that
are
characterisBc
for
its
species.
• –
The
four
stages
in
a
complete
metamorphosis
life
cycle
are
the
egg,
the
larva,
the
pupa,
and
the
adult.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
Almost
all
insect
species
undergo
complete
metamorphosis.
99

100. November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
100

101. Subphylum
Uranimia
Class
Insecta
• Insects
are
successful
because
– Of
numbers.
More
species
than
all
other
classes
of
animals
combined.
(what
the
lack
in
size,
they
make
up
in
sheer
numbers)
– They
have
an
extra
ordinary
ability
to
adapt
to
changes
in
the
environment
(Believed
they
can
inherit
the
earth)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
101

102. Subphylum
Uranimia
Class
Insecta
SECRETS
OF
THEIR
SUCCESS
– Body
plan
modified
and
specialized
in
so
many
ways
that
insects
have
been
able
to
adapt
to
an
incredible
number
of
life
styles
– They
have
filled
almost
every
variety
of
ecological
niche
– Their
ability
to
fly
rapidly
through
the
air
• Wings
and
small
size
facillitate
their
wide
distribuEon
– Body
is
well
proteced
by
tough
exoskeleton,
which
also
helps
to
prevent
water
loss
by
evaporaEon
– ProtecEve
mechanism
such
as
mimcry,
protecEve
coloraEon
and
aggressive
behavior
– Metamorphosis
divides
the
insect
into
different
stages
•
a
strategy
that
has
the
advantage
of
placing
larval
forms
into
their
own
niches
so
that
they
do
not
have
to
compete
with
adults
for
food
or
habitats.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
102

103. Subphylum
Uranimia
Class
Insecta
– Tremendous
numbers
of
species
largely
ajributed
to
the
feeding
specializaEon,
dispersal
capabiliEes
and
predaEon
avoidance
possibiliEes
associated
with
evoluEon
of
flight
(no
other
invertebrate
and
relaEvely
few
vertebrates
sp.,
have
evolved
this
capability)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
103

104. Subphylum
Uranimia
Class
Insecta
SOCIAL
INSECTS
• What
are
the
characterisBcs
of
social
insects?
• Social
insects
have
elaborate
social
systems
involving
specializaBon
of
labor,
parental
care,
and
communicaBon
between
individuals.
– The
role
that
an
individual
plays
in
a
colony
is
called
a
caste.
– Caste
is
determined
by
a
combinaBon
of
heredity,
diet,
hormones,
and
pheromones.
– Social
insects
include
honeybees
and
termites.
– A
honeybee
hive
contains
a
queen,
workers,
and
drone
males.
– Termites
have
kings
as
well
as
queens.
Workers
gather
the
food,
raise
the
young,
and
excavate
tunnels.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
104

105. Subphylum
Uranimia
-­‐
Class
Insecta
Female
caste
members
of
termites
(a)
Queen
(b)
Worker
(c)
Soldier
(d)
Secondary
queens
(e)
TerEary
queen
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
105

106. Subphylum
Uranimia
Class
Insecta
• Insect
social
systems
encompasses
many
important
issues
in
behavioral
ecology
and
evoluEonary
theory
• Many
hymenopterans
(ants,
bees,
wasp,
termits)
are
eusocial
(true
social
insects)
– They
form
colonies
composed
of
more
or
less
sterile
workers
and
one
or
more
reproducEve
queens.
• Queens
exhibit
mulEple
generaEons
within
a
colony
(protected
and
cared
for
by
her
offsprings)
• Queens
aler
maEng
loose
their
wings
and
build
nests
where
she
then
lays
eggs
who
forms
the
worker
caste.
November
9,
2012
– Workers
take
care
of
the
nest,
care
for
the
embryos
and
larvae,
defend
the
nest
and
forage
for
food.
– Some
workers
develop
into
soldiers,
morphologically
and
behaviorally
106
specialized
for
ABCS
101
(Introductory
Animal
Biology)
defense
and
aggression.

107. Subphylum
Uranimia
Class
Insecta
• CommunicaEon
is
through
a
complex
system
of
mechanical
and
chemical
cues.
• Males
are
produced
only
aler
the
colony
has
achieved
a
substanEal
size,
aler
several
years.
– The
queen
produces
males
delibrately,
by
releasing
eggs
without
ferElizing
them
(haploid-­‐
pathogeneEcs)
» Winged,
do
no
work
and
are
chased
out
of
the
colony
by
workers
• Some
diploid
embryo
however
develop
into
winged
reproducEves
(future
queens)
– the
quality
of
food
and
hormonal
Etres
are
altered
• Males
dies
soon
aler
maEng
and
queens
develop
new
nests
thus
iniEaEng
new
colonies
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
107

108. Subphylum
Uranimia
Class
Insecta
• Bees
also
exhibit
social
behaviors
– Workers
are
always
diploid
females
• Care
for
queens
and
offsprings,
scouEng
out
suitable
nest
sites,
and
controlling
nest
temperature
– These
roles
change
as
workers
age
(and
exhibit
altered
hormonal
concentraEons)
– Males
are
always
haploid,
do
no
work
and
are
eventually
expelled.
– Queens
mate
briefly
and
store
enough
eggs
to
last
a
life
Eme.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
108

109. Subphylum
Uranimia
Class
Insecta
• Unlike
ants
and
bees
termits
queens
cannot
control
the
sex
of
their
offsprings
– Workers
may
be
males
or
females
• Both
sterile
and
blind
– Workers
in
primiEve
species
are
made
up
of
developmentally
arrested
larval
stages
called
Pseudergates
(“false
workers”)
• These
can
remain
workers
for
life
or
metamorphose
into
winged
reproducEves
and
find
new
colonies,
or
into
soldiers
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
109

110. Subphylum
Uranimia
Class
Insecta
DIVERSITY
• Two
sub
class
– Apterygota-­‐wingless
insects
• Order
Thysanura-­‐
silverfish
or
bristletail
• Order
Collembola-­‐
springtail
– Pterygota-­‐
winged
insects
• Abt
29
0rders
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
110

111. • Psocoptera
(book
lice,
bark
lice)
Protura
(small,
wingless
insects)
• Mallophaga
(biEng
lice)
Collembola
(springtails)
• Siphunculata
(sucking
lice)
Thysanura
(silverfish)
• Hemiptera
(true
bugs)
Diplura
(bristletails)
• Thysanoptera
(thrips)
Ephemeroptera
(mayflies)
• Neuroptera
(lacewings,
antlions,
Odonata
(dragonflies,
damselflies)
manEs
flies)
Plecoptera
(stoneflies)
• Coleoptera
(beetles)
300
000
spp
Grylloblatodea
(grylloblajas)
• Strepsiptera
(stylops)
Orthoptera
(crickets,
grasshoppers,
• Mecoptera
(scorpionflies)
locusts)
• Siphonaptera
(fleas)
• Phasmida
(sEck
insects,
leaf
insects)
• Diptera
(true
flies,
mosquitoes)
• Dermaptera
(earwigs)
• Lepidoptera
(bujerflies,
moths)
200
• Embioptera
(embiids)
000
spp
• Dictyoptera
(cockroaches,
manEds)
• Trichoptera
(caddis
flies)
• Isoptera
(termites)
• Hymenoptera
(bees,
ants,
wasps,
111
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
• Zoraptera
(terrestrial
lice)
hornets)
100
000
spp
•
•
•
•
•
•
•
•
•

112. Subphylum
Uranimia
Class
Insecta
•
•
•
•
•
•
•
•
•
November
9,
2012
(a)
An
aperygote
(b)
frui~ly
(c)
leaf
cujer
(d)
mosquito
(e)
Bujerfly
(f)
Termites
(g,h)
beetles
(i)
grasshopper
(J)
larvae
of
a
caddisly
ABCS
101
(Introductory
Animal
Biology)
112

113. Subphylum
Uniramia
Class
Insecta
Insect
diversity
• Insect
orders
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
113

114. Insect
order
populaEons
in
relaEon
to
life
on
earth
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
114

115. ARTHROPODA
Subphylum
Crustacea
Class
Malascostraca
Class
Ostracoda
Class
Copepoda
Class
Cirripedia
Class
Pentastomida
(Biramous
appendages:
branched
appendage
with
2
pairs
of
antennae)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
115

116. SUBPHYLUM
CRUSTACEANS
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
116

117. CRUSTACEANS
– bilateral
symmetry
–
eucoelomic
(true
coelom)
–
high
degree
of
cephalizaEon
=
well
developed
head
with
sensory
organs
–
specialized
segmentaEon
(metamerism)
=
tagmata
– triploblasEc
structure
(endoderm,
mesoderm
and
ectoderm)
– all
organ
systems
are
present
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
117

118. SUBPHYLUM
CRUSTACEANS
CRUSTACEANS
• Like
chelicerates,
crustaceans
have
appendages
on
their
abdomen
• Unlike
chelicerates,
crustaceans
have
mandibles
that
are
adapted
for
feeding
and
have
two
antennae
– Some
crustaceans
are
sessile,
which
means
that
they
are
permanently
ajached
to
something.
• Barnacles
are
an
example
of
a
sessile
crustacean.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
118

119. most
crustaceans
have
between
16
and
20
segments
some
have
many
more
• !
different
segments
in
different
groups
may
have
fused
to
form
a
head
or
cephalothorax
•
crustaceans
have
a
cephalothorax
and
an
abdomen
• !
head
fused
to
thoracic
body
segments
to
form
a
cephalothorax
• !
abdomen
is
formed
of
the
posterior
segments
• !
telson
(tail)
with
uropod
• !
first
walking
leg
is
chelate
(cheliped)
• !
two
pairs
of
antennae
(one
pair
of
antennae
and
one
pair
of
ABCS
101
(Introductory
Animal
Biology)
119
antennules)
•
November
9,
2012

120. SUBPHYLUM
CRUSTACEANS
• The
two
pairs
of
antennae
are
the
sites
of
chemoreceptor
and
tacEle
sense
organs,
the
2nd
pair
of
antennae
are
especially
long.
• !
one
pair
of
mandibles
(crustaceans
are
the
aquaBc
mandibulates)
– Mandibles
are
short
and
heavy
with
the
opposing
surface
used
in
grinding
and
biEng
of
food
• !
two
pairs
of
maxillae
on
the
head
– Behind
the
mandibles
are
two
pairs
of
accessory
feeding
appendages,
the
first
and
second
maxillae.
• The
appendages
of
the
first
3
segments
of
the
thorax
are
the
maxillipeds,
which
aid
in
chopping
up
food
and
passing
it
to
the
mouth.
• The
4th
segement
of
the
thorax
has
a
pair
of
large
chelipeds
or
pinching
claws
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
120

121. SUBPHYLUM
CRUSTACEANS
• The
last
four
thoracic
segments
have
pairs
of
walking
legs
• The
appendages
of
the
first
abdominal
segment
are
part
of
the
reproducEve
system
and
funcEon
in
the
male
as
sperm
–
transferring
structures.
• The
four
abdominal
segements
are
paired
swimmerets,
small
paddle-­‐like
structures
used
by
some
decapods
for
swimming
and
by
females
of
all
species
for
holding
eggs.
• Each
branch
of
the
sixth
abdominal
appendages
which
are
called
uropods;
consists
of
a
large
flajened
structure
together
with
the
flajened
telson,the
posterior
end
of
the
abdomen,
they
form
a
fan-­‐shaped
tail
fin
used
for
swimming
backwards.
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
121

122. • !
usually
one
pair
of
appendages
on
each
body
segment
• !
all
appendages
except
the
first
pair
of
antennae
in
present-­‐day
crustaceans
are
biramous
(two-­‐branched)
•
• !
body
is
covered
with
secreted
cuBcle
of
protein,
chiBn
and
calcareous
material
• !
cuBcle
is
thinner
around
joints
for
movement
– !
tergum
is
the
dorsal
cuBcle
plate
on
each
segment
not
covered
by
carapace
– !
sternum
is
the
ventral
cuBcle
on
each
segment
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
122

123. – Almost
all
crustaceans
have
a
disEncEve
larval
form
called
a
nauplius.
– Isopods
are
the
only
crustaceans
that
are
truly
terrestrial.
Pill
bugs
are
examples
of
isopods.
– Some
aquaEc
crustaceans
are
quite
small.
• Common
examples
include
fairy
shrimps,
water
fleas,
and
copepods.
– Another
small
marine
crustacean,
commonly
known
as
krill,
is
the
chief
food
source
for
many
marine
species.
•
•
•
•
•
mainly
marine,
many
freshwater,
a
few
are
terrestrial
!
Class
Malacostraca
is
the
largest
group
(lobsters,
crabs,
shrimps,
beach
hoppers
and
many
others)
!
walking
legs,
mouthparts,
chelipeds
and
swimmerets
have
all
become
modified
for
different
funcEons
from
a
common
biramous
appendages
(they
are
serially
homologous)
!
crustaceans
have
segmented
nervous
and
muscular
systems
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
123

124. • Senses
sense
organs
include:
compound
eyes
formed
of
ommaBdia,
tacBle
hairs
(especially
• on
chelae
and
mouthparts
and
telson);
chemoreceptors
for
taste
and
smell
on
• antennae,
mouthparts
and
other
places;
statocysts
open
on
dorsal
side
at
the
base
of
• each
first
antennae
(in
crayfish)
with
chiEnous
lining
and
sand
grains
that
act
as
• statoliths
which
are
replaced
a]er
each
molt
• !
Each
hexagonal
ommaBdia
of
the
eye
is
covered
by
a
transparent
part
of
the
cuBcle
=
• cornea;
each
ommaBdia
acts
as
a
“Bny
eye”
with
pigment
cells
between
them
that
• form
a
collar
to
separate
ommaEdia;
in
bright
light,
each
ommaBdia
only
“sees”
a
• limited
area
of
the
field
of
view
to
form
a
mosaic
image;
at
night,
distal
and
• proximal
pigment
cells
can
separate
so
light
hits
mulBple
reBnal
cells
in
mulBple
• ommaEdia
to
form
a
superimposed
conEnuous
image
that
is
not
mosaic,
but
less
November
9,
2012
ABCS
1
124
• precise
–
this
makes
the
most
o01
(he
limited
available
light
at
night
f
t Introductory
Animal
Biology)
•

125. • Feeding
• Feeding
Habits
of
Crustaceans
• !
much
variaEon
in
feeding
habits
of
crustaceans
and
some
can
shil
feeding
strategies
(eg.
• pistol
shrimp
use
their
enlarged
chela
to
snap
shut
very
fast
and
form
a
cavitaEon
bubble
• that
can
stun
prey)
• !
chelipeds
are
used
in
prey
capture
and
mandibles
and
maxillae
and
other
mouthparts
used
• in
ingesEng
food
• !
crustaceans
can
be
suspension
feeders,
predators
or
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
125
scavengers

126. • ExcreEon
•
•
•
•
•
•
•
•
•
•
•
•
green/antennal
or
maxillary
glands
depending
on
where
they
open
at
are
paired
tubular
structures
for
excreEon;
crustaceans
lack
Malpighian
tubules
!
freshwater
crustaceans
have
green
glands
that
form
a
dilute
low-­‐salt
urine
for
osmoEc
balance;
some
salt
is
lost
with
the
urine
but
is
replaced
by
salt
absorpEon
through
the
gills
(lijle
nitrogenous
waste
is
actually
excreted
by
the
green
glands)
!
excreBon
of
primarily
ammonia
occurs
primarily
by
diffusion
across
thin
areas
of
the
cuBcle
and
gills
!
marine
crustaceans
have
kidneys
for
salt
and
water
balance
(osmoregulaBon)
!
nervous
system
is
composed
of
a
pair
of
supraesophageal
ganglia
with
nerves
to
the
eyes
and
two
pairs
of
antennae
which
is
joined
to
a
subesophageal
ganglion
with
nerves
to
the
mouth,
appendages,
esophagus
and
antennal
glands;
paired
ventral
nerve
cords
with
a
pair
of
ganglia
in
each
segment
and
peripheral
nerves
to
appendages,
•
muscles,
etc
November
9,
2012
.
ABCS
101
(Introductory
Animal
Biology)
126

127. RESPIRATION
• Crustaceans
breathe
by
using
gills
• !
efficient
gills
for
respiraBon
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
127

128. • CirculaEon
• “open”
circulatory
system
with
blood
leaving
the
dorsal
heart
through
short
arteries
• to
the
hemocoel
and
back
to
the
heart
through
venous
sinuses;
arteries
possess
valves
• to
prevent
backflow
• !
hemolymph
may
be
colorless,
reddish
or
bluish
due
to
hemocyanin
(copper
containing
• respiratory
pigment
or
hemoglobin
(iron
containing
respiratory
pigment);
hemolymph
• can
clot
to
prevent
loss
in
minor
injuries
and
ameboid
cells
release
November
9,
2012
clopng
proteins
(Introductory
Animal
Biology)
ABCS
101
128

129. ReproducEon
•
gonopore
posiBon
varies
usually
near
the
5th
pair
of
walking
legs
in
males
&
the
3rd
pair
of
walking
legs
in
females;
opening
to
the
seminal
receptacle
is
near
the
4th
and
5th
pairs
of
walking
legs
in
females
• !
considerable
specializaEon
of
appendages
has
occurred
in
many
derived
groups
such
as
the
crayfishes
•
•
•
•
•
•
•
•
most
crustaceans
have
separate
sexes
with
specializaBons
for
copulaBon
and
ways
of
brooding
their
eggs
!
barnacles
are
monoecious
but
uBlize
cross-­‐ferBlizaBon
with
other
individuals
via
a
very
long
penis
(relaEve
to
body
size)
as
sessile
adults
!
ostracods
and
some
copepods
are
o]en
parthenogeneBc
!
the
ancestral
most
common
type
of
larva
in
crustaceans
is
a
nauplius
larva
with
three
pairs
of
appendages,
uniramous
first
antennules,
biramous
antennae
and
biramous
mandibles
all
used
for
swimming
with
gradual
changes
to
an
adult
form
through
a
•
series
of
molts
or
only
a
fews
molts
(eg.
barnacles)
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
129

130. SUBPHYLUM
CRUSTACEANS
•
•
•
•
•
•
Class
Malacostraca
Class
Branchiopoda
Class
Ostracoda
Class
Copepoda
Class
Pentastomida
Class
Cirripeda
November
9,
2012
ABCS
101
(Introductory
Animal
Biology)
130