Transcript ZOO 115 Invertebrate Zoology

ZOO 115 Invertebrate Zoology
Phylum Arthropoda
Subphylum Chelicerata
Subphylum Chelicerata
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Includes spiders, horseshoe
crabs, seas spiders and
scorpions
Cephalothorax
Have only two tagmata:
cephalothorax and the abdomen
Abdomen
Subphylum Chelicerata
Cephalothorax bears 6
pairs of appendages
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Chelicera are on
the 2nd
cephalothorax
segment
Pedipalps
4 pr walking legs.
Do not have
antennae and
deutocerebrum
Abdomen has 12 or
fewer segments
Pedipalp
Chelicerae
Subphylum Chelicerata
Class Xiphosura
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Horseshoe crabs
Up to 75 cm (largest
chelicerates)
Live in marine shallow
water on soft bottoms
Omnivores
Toxic (lethal) to Predators
– saxotoxin in tissues
Vestigial coelom = body
cavity is hemocoel
http://www.globalclassroom.org/hcrab2.jpg
Subphylum Chelicerata
Class Xiphosura - Anatomy
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6 pair of
appendages
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1 pr
Chelicera
4 pr chelate
legs
1 pr pusher
legs
Carapace
Telson
Chelate walking legs
Compound eye
Median eyes
Pusher leg
http://mainegovimages.informe.org/dmr/rm/aquarium/teachers_guide/horseshoe_crab_dorsal_vie
w.jpg
Subphylum Chelicerata
Class Xiphosura - Feeding
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Uses chelate
walking legs and
chelicera to
capture food.
Transferred to the
food groove
Base of
appendages are
grinding surfaces
(gnathobases)
Spines on
appendages move
food to mouth
Mouth
Food
http://mainegovGnathobase
images.informe.org/dmr/rm/aquarium/teachers_guide/horseshoe_crab_dorsal_vie
w.jpg
Subphylum Chelicerata
Class Xiphosura - Feeding
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Mouth to crop
Transferred to
muscular toothed
gizzard
Moves to stomach
Digestable material
to digestive pouch
Other material to
intestine
Solid waste outside
via anus
Intestine
Stomach
Gizzard
Solid waste
Crop
Food
Digestive pouch
http://mainegovimages.informe.org/dmr/rm/aquarium/teachers_guide/horseshoe_crab_i
nternal_anatomy.jpg
Subphylum Chelicerata
Class Xiphosura - Gas Exchange
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Water moves in
through space
between the
abdominal plate
and the
carapace
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Then moves
across gills and
out
Gills
http://mainegovimages.informe.org/dmr/rm/aquarium/teachers_guide/horseshoe_crab_internal_anatomy.
jpg
Subphylum Chelicerata
Class Xiphosura - Circulation
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Blood flows into
heart (via ostia)
Pumped through
arterial system
Into hemocoel
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Through gills
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Back to heart
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Heart
Pericardial sinus
http://mainegovimages.informe.org/dmr/rm/aquarium/teachers_guide/horseshoe_crab_i
nternal_anatomy.jpg
Subphylum Chelicerata
Class Xiphosura – Nervous system
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Large brain
Compound lateral eyes
Pair of median pigment cup ocelli
Rudimentary ventral eye
Sensilla
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mechanoreceptors
chemorecepetors
osmoreceptors
Subphylum Chelicerata
Class Xiphosura – Reproduction
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Gonochoric
Sexual dimorphic – male
smaller
Mating during exceptionally
high tides of full and new
moons during Spring and
Summer
Female deposits 2000-30000
eggs into sand
Male fertilizes eggs
Have a trilobite larva
http://www.lander.edu/rsfox/310limulusLab_files/image020.jpg
Subphylum Chelicerata – Class
Arachnida
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Includes spiders,
scorpions, mites and
ticks
~70,000 described
sp. but maybe a
million more
Mostly carnivores
Subphylum Chelicerata
Class Arachnida - Anatomy
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Appendages
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Cheliceae
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Pedipalps
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Sometimes
with poison
or silk
Many
functions
4 pr walking
legs
Pedipalp
Chelicera
http://www.rochedalss.eq.edu.au/spider/spideran.gif
Chelicera
Subphylum Chelicerata
Class Arachnida - Digestion
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Small digestive
tube
Digestion starts in
preoral cavity
formed by
appendages and
carapaceproteolytic
enzymes
Either the
stomach or
pharynx is a
muscular pump
http://www.rochedalss.eq.edu.au/spider/spideran.gif
Subphylum Chelicerata
Class Arachnida –Circulation
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Trachae
Book lungs
Subphylum Chelicerata
Class Arachnida – Gas Exchange and
circulation
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Gas Exchange
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Trachae
Book lungs
Circulation
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Hemocoel
Book lungs
Heart
Arterial
system
Back to
hemocoel
http://www.sci.sdsu.edu/classes/bio201/book%20lung.gif
Subphylum Chelicerata
Class Arachnida – Excretion
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Excrete quanine, adenine,
xanthine or uric acid
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Allows little loss of water
Two systems
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Nephridia
Malphigian tubules
Subphylum Chelicerata
Class Arachnida – Nervous system
Brain
http://instruct1.cit.cornell.edu/courses/bionb424/students2004/leb27/CNSsmall.jpg
Subphylum Chelicerata
Class Arachnida – Nervous system
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Sensory
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Compound eyes – small but greater number
Sensory setae – major sense organs
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Mechanoreceptors
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Trichbothria – specialized for sensing weak air
movement.
Chemoreceptors
Slit sense organs – strain gauges for cuticle
No antennae but often equivalent on legs
Class Arachnida - Diversity
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Order Scorpiones
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3-21 cm in length
Greatly enlarged
pedipalps
Very small
chelicerae
Stinger
Predators – stay
near burrow
http://www.thedailylink.com/thespiralburrow/anatomy/anat02.html
Can sting http://www.regalreptile.com/scorpion%203.jpg
within 0.75 sec.
Class Arachnida - Diversity
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Order Scorpiones
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http://www.thedailylink.com/thespiralburrow/anatomy/anat02.html
Gonochoric
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Mature – 6 yrs
Extended courtship
ritual
Indirect sperm transfer
– spermatophores
Viviparous
Care of young
Direct development –
months
Live up to 25 yrs
http://cals.arizona.edu/pubs/insects/az1320/Female-bark-scorpionalt.jpg
http://www.regalreptile.com/scorpion%203.jpg
Class Arachnida - Diversity
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Order Uropygi
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Whip scorpions or
Vinegaroons
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80 mm in length
Cephalothorax
completely covered by
carapace
Pair anterior median
eyes
3-4 pairs lateral eyes
Small chelicerae
Large chelate
pedipalps
http://www.petbugs.com/caresheets/gallery/M-giganteus.jpg
Class Arachnida - Diversity
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Order Uropygi
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2 pair book lungs
Pair of large
repugnatorial glands
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84% acetic acid and
5% caprylic acid
1st leg acts as
antennae
Gonothropic
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Complex courship
Indirect sperm transfer
- spermatophore
http://www.petbugs.com/caresheets/gallery/M-giganteus.jpg
Class Arachnida – Diversity
Order Amblypygi
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Whip spider
1st legs – antennae
All legs sensory
Anatomy similar to
spiders:
 Chelicerae similar to
spiders but lack
poison glands.
repugnatorial glands
 No silk produced
Tends to move laterally
Indirect sperm transfer spermatophore
http://www.amnh.org/exhibitions/hall_tour/spectrum/specimens/
a2395h.jpg
Class Arachnida – Diversity
Order Araenae
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Spiders
0.5 mm to 9 cm in length
~40,000 described sp, ~130,000
undescribed sp.
Males usually smaller than females
Three groups based
 Most Primitive
 Primitive chelicerae (only
longitudinal movement)
 Segmented abdomen
 Primative
 Primitive chelicerae
 Advanced
 Fangs can move to oppose each
other
Class Arachnida – Diversity
Order Araenae – Silk
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What is it?
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Made of glycine, alanine and
serine
6-8 different kinds
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0.003 mm thick
Cribellum
Silk glands – different kinds
Spinnerets
 Single thread composed of
many fibers which are
weaved together
Cribellum – not in all
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5-6 used by any one spider
Produced by
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http://www.dmns.org/main/minisites/spiders/idkey1.html
http://www.dmns.org/main/minisites/spiders/idkey1.html
Anterior to spinnerets
Fine silk used for prey
capture
Spiders eat silk to reclaim it
Silk glands
Spinnerets
//www.astrographics.com/GalleryPrints/Display/GP2017.jpg
Class Arachnida – Diversity
Order Araenae – Silk
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Function
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Reproduction
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Sperm web
Egg case
Nests
http://citybugs.tamu.edu/
FastSheets/images/spider
-ballooning.gif
Dragline
Dispersion
Prey capture (webs)
http://www.museums.org.za/bio/spiderweb/reproduction.htm
http://www.washington.edu/burkemuseum/spidermyth/images/
draglinethumb.jpg
http://typhoon.wcp.muohio.edu/tropicalvideos/
costarica03/spidereggcase03.jpg
Class Arachnida – Diversity
Order Araenae – Prey capture
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Web builders
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Orbs
 Only the spiral is sticky
 Walk on radial
Tarantula
 Built to catch specific
types of insects
 Affected by food
Tunnel or Trapdoor
http://www.bushveld.co.za/pic
tures-arachnids/garden-spiderlarge.jpg
Hunting
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Heavier legs
Good eyes in many
http://mamba.bio.uci.edu/~pjbryant/biodiv/spiders/Ap
http://www.1000plus.com/alex/ImageGallery/Arachnids%20honopelma%20reversum.htm
%20Spiders/tn/Tunnel%20Spider.jpg.html
http://www.coffee.co.uk/spiders.html
http://www.nancylynne.com/Spider%
20Web%20for%20web.jpg
Class Arachnida – Diversity
Order Araenae – Prey capture
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Scopulae – walk up
walls or glass
Best developed slit
sensors on legsvibration
Eyes
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Main
Secondary
http://dine.sanjuan.k12.ut.us/heritage/land/animals/bugs/images/w
olf_spider.jpg
http://www.dal.ca/~egingl/research.htm
http://research.amnh.org/entomology/blackrock2/images/main_key/
scopulae_philodromidae.gif
Class Arachnida – Diversity
Order Araenae – Prey capture
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Fangs
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Movement
http://www.geocities.com/spiders_snakes/spider/fang.jpg
Toxin
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Hunters – cytotoxin
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antibiotics usually
required
no anti-venom
anti-tetanus injection
Some patients
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In 3 days mild fever,
headaches
The above victim saw the Brown Recluse
Brown Recluse or Violin spider
spider on her foot as she got out of the
shower. This leg no longer exists because
she had to have it amputated below the
knee.
http://static.howstuffworks.com/gif/spider-fang.gif
http://www.museums.org.za/bio/spiderweb/bites.htm
http://www.brown-recluse.com/index.html?google1
Class Arachnida – Diversity
Order Araenae – Prey capture
Black Widow
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Fangs
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Movement
Toxin
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Web-builders – neurotoxin
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severe pain in the chest
and abdomen
anxiety, raised blood
pressure
breathing difficulties and
heart palpitations
nausea and vomiting
sweating, excessive
salivation and watery eyes
a rash might develop
Trachoma
Funnel-Web Spider
LETHAL
Atrax
Funnel-Web spider
LETHAL
http://acd.ufrj.br/mndi/Aracnologia/Trechona.htm
http://www.dobrodruh.cz/data/bookimg/00363-atrax.jpg
http://library.thinkquest.org/C007974/media/2_
4bla.jpg
Class Arachnida – Diversity
Order Araenae – Prey capture
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Fangs
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Movement
Non-Toxic
http://www.ambergriscaye.com/pages/photos/art/tarantula.jpg
Class Arachnida – Diversity
Order Araenae – Digestion
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Either totally
dissolve prey with
enzymes or
masticate
Fluid sucked into
midgut passing
through particle
filters
Digested in Caeca
Class Arachnida – Diversity
Order Araenae – Gas Exchange
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Book lungs
And/or tracheae
Class Arachnida – Diversity
Order Araenae – Reproduction
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Gonochoric
Indirect sperm
transfer
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No spermatophores
Transferred by
pedipalps
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Male spins sperm
web (shown earlier)
Deposits sperm on
web
Transfers sperm to
pedipalps
Pedipalps transfer
sperm to female
Class Arachnida – Diversity
Order Solifugae
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Sun spider
~800 species
2 mm – 7 cm
Inhabit warm arid regions
Enormous chelicerae
No venom
1st legs used as antennae
Males extremely fast
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Highly developed tracheae
http://www.key-net.net/users/swb/pet_arthropod/SS.jpg
Class Arachnida – Diversity
Order Opilones
Spider leg
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Daddy long-legs or
Harvestman
~5000 species
5 mm – 22 cm body
No venom
No constriction between
cephalothorax and
abdomen
Long legs because of a
multisegmented tarsus
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May have 100s
Eyes on Tubercle
http://troyb.com/photo/images/photos/00012918.jpg
http://www.thelensflare.com/large/spider_979.jpg
http://www.xs4all.nl/~ednieuw/Spiders/Info/spiderinfo.htm
Class Arachnida – Diversity
Order Acari
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Ticks and mites
~40,000 described
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Gnathosoma
0.1 – 0.75 mm length
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>1,000,000 undescribed
http://www.sdm.buffalo.edu/scic/toms_tick/tick-2_full.jpg
Smallest can live in
tracheae of honeybee
Present in all habitats
tagmata different
No segmentation
Entire body covered with
single carapace
Idiosoma
Pedipalp
http://www.uky.edu/Agriculture/Entomology/entfacts/st
ruct/amdogtik.gif
Class Arachnida – Diversity
Order Acari
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Large diversity in
feeding
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Carnivores
Herbivores
Scavengers
Ectoparasites
Endoparasites
Chelicera
Pedipalp
http://www.ijon.de/zecken/images/i-hex-wg.gif
http://www.uky.edu/Agriculture/Entomology/entfacts/st
ruct/amdogtik.gif
Class Arachnida – Diversity
Order Acari
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Nervous system
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Sensory setae
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Air currents
Heat
Chemo
Mechano
Median and lateral
eyes
Slits on legs that may
be analogous to slit
sense organs
http://www.uky.edu/Agriculture/Entomology/entfacts/st
ruct/amdogtik.gif
Class Arachnida – Diversity
Order Acari
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Reproduction
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Gonochoric
Indirect sperm transfer
by spermatophore
Transferred by
chelicera, male 3rd pr.
legs or female may
pick up.
Eggs in soil or humus
2-6 wk incubation
http://www.uky.edu/Agriculture/Entomology/entfacts/st
ruct/amdogtik.gif