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4/14/2016
Bio 125 Lecture #22: 4/14/16
Reminder: Field trip for lab next weekCarpinteria Salt Marsh. Lab begins & ends there
Direction on p 1 of lab
WOD: placoid scale
I. Phylum Chordata, Subphylum Vertebrata,
Class Chondrichthyes (cartilaginous fishes) con’t
A. Subclass Elamsmobranchii (sharks, rays, etc)
1. Reproduction
2. Ray & skate body plan
B. Subclass Holocephali (ratfish, chimeras)
II. Class Sarcopterygii (lobe-finned fishes)
III. Class Osteichthyes: Bony Fishes
A.
Distinguishing Characteristics (9)
B.
Locomotion
1. Muscles
2. Fins
C.
Coloration
D.
Respiration - counter current gas exchange
Phylum Chordata, Class Chondrichthyes
Rays & skates: benthic
Chondrichthyes Reproduction:
1. Ovipary
2. Ovovivipary
2. (skates, swell, horn sharks) (Most common)
3. Vivipary
(requiem sharks)
Phylum Chordata, Class Chondrichthyes
Rays & skates -midwater
Devil ray
Spotted eagle ray
manta ray
Phylum Chordata, Class Chondrichthyes
Subclass Holocephali (ratfish & chimeras)
Phylum Chordata, Class Sarcopterygii
Coelocanths (lobe-finned fishes)
http://whyevolutionistrue.wordpress.com/2009/09/28/thats-notratfish-genitalia-thats-ratfish-genitalia/
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Osteichthyes: bony fishes
Distinguishing Characteristics of Bony Fishes
1. Bony skeleton
Preps & Photos: Steve Huskey, LKU
Distinguishing Characteristics of Bony Fishes
2. Scales (in most)
- thin, flexible, overlapping
Ctenoid Scales –
spiny border
Cycloid Scales - smooth
Ctenoid scales of a Paradise Fish, Macropodus opercularis.
Photographer:Sue Lindsay
© Australian Museum
Distinguishing Characteristics of Bony Fishes
3. Single gill slit covered by an operculum
A freshwater digression:
Arapaima gigas
http://news.sciencemag.org/sciencenow/2012/02/a-piranha-proof-fish.html?ref=em
Distinguishing Characteristics of Bony Fishes
4. Homocercal caudal fin
Vs. Chondricthyes:
Heterocercal tail
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Distinguishing Characteristics of Bony Fishes
5. Fin rays
Distinguishing Characteristics of Bony Fishes
6. Mouth - terminal
Vs. Chondricthyes:
Stiff, cartilagenous fins
Distinguishing Characteristics of Bony Fishes
Vs. Chondricthyes:
Ventral mouth
Distinguishing Characteristics of Bony Fishes
8. Teeth attached to jawbone
7. Protrusible jaws
Key to success
vs. Chondrichthyes: embedded in flesh
http://www.youtube.com/watch?v=m2lcBaqYK1o
Distinguishing Characteristics of Bony Fishes
Distinguishing Characteristics of Bony Fishes
9. Swimbladder (in most)
10. Awesome diversity!
Shapes, lifestyles, behaviors..
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Bony Fish Locomotion
Myomeres:
1. Musculature
bands of muscles
Coloration
Chromatophores:
pigment cells in skin
Iridophores:
Crystals – reflect light
Fish can be up to 75% muscle!
Coloration
Coloration
2. disrupt outline;eyes spots
1. Camouflage: Match background
Counter-shading
Coloration
3. Advertise
Osteichthyes: Respiration
Gill chamber
Gill arches: support gills
Gill filaments
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Osteichthyes: Respiration
Lecture #22 (4/14/16): Study Questions
1. How can you distinguish the gender of
Chondrichthyes?
2. What about the life cycle of Chondrichthyes
makes them vulnerable to overfishing?
3. Name & describe the 3 different methods of
reproduction found within Class
Chondrichthyes.
4. Which reproductive mode of Chondrichthyes
is most common?
5. List 2 ways that rays & skates differ from
sharks.
6. List 7 characteristics of Subclass Holocephali
(ratfishes/chimeras).
7. Describe a physical characteristic of coelacanths
(Class Sarcopterygii) that indicates an evolutionary
link with tetrapods (4-legged animals).
8. What habitat do coelacanths require?
9. List 9 distinguishing characteristics of Class
Osteichthyes (bony fishes).
10. List 4 properties of bony fish scales.
11. How are the scales of Arapaima structurally
different from other fish? What is the benefit of this
structure?
12. What advantages do protrusible jaws provide?
13. Bony fish can be up to _____% muscle. Why
so much?
14. Describe 2 different ways fish can camouflage.
15. Describe respiration in fishes, including how
they maintain a maximum of oxygen absorption
from the water.
16. Describe the anatomy of a fish gill, defining
the following terms: operculum, gill arches, gill
rakers, gill filaments, lamellae.
17. Define: clasper, cycloid scale, ctenoid scale,
myomere, chromatophores, iridophore, gill arch,
gill filament, gill rakers, fish operculum,
homocercal, protrusible jaw, swim bladder
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