Skelton & MusclesSkelton & Muscles
HagfishHagfish
No true vertebrae - sheath of cartilage surrounding notochord
Few skull bones
No true vertebrae - sheath of cartilage surrounding notochord
Few skull bones
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Lamprey skeletonLamprey skeleton
Cartilaginous- limited skull- branchial basket
Chondrichthyes skeletonChondrichthyes skeleton
Cartilaginous-limited skull - 3 parts (chondrocranium, jaws, branchial cartilages)
Chondrichthyes skeletonChondrichthyes skeleton
Cartilaginous-Pectoral, pelvic girdles, fin support
Osteichthyes skeletonOsteichthyes skeleton
Osteichthyes skeletonOsteichthyes skeleton
Solid bone with complete vertebral column Simple vertebrae that lack interlocking processes One vertebra per body segment - match with
muscle masses for coordinated swimming movements
Solid bone with complete vertebral column Simple vertebrae that lack interlocking processes One vertebra per body segment - match with
muscle masses for coordinated swimming movements
Osteichthyes skeletonOsteichthyes skeleton
Vertebrae modified anteriorly for skull articulation, posteriorly for caual fin articulation
Specialized anterior vertebraeSpecialized anterior vertebrae
Posterior vertebraePosterior vertebrae
Better view of posterior vertebrae
Better view of posterior vertebrae
Trunk vertebraeTrunk vertebrae
Vertebrae in middle are trunk vertebrae of two kinds:those with ribs and those without
VertebraeVertebrae
Vertebrae without ribs
Dorsal process Neural arch with
neural spine Neural canal for
spinal cord
Vertebrae without ribs
Dorsal process Neural arch with
neural spine Neural canal for
spinal cord
VertebraeVertebrae
Ventral process Hemal arch with
hemal spine Hemal canal for
primary blood vessels (arteries, veins)
Ventral process Hemal arch with
hemal spine Hemal canal for
primary blood vessels (arteries, veins)
Spines provide supportSpines provide support
Neural and hemal spines provide support for body musculature
Especially long in laterally compressed teleost fishes
“Double comb” appearance
Neural and hemal spines provide support for body musculature
Especially long in laterally compressed teleost fishes
“Double comb” appearance
VertebraeVertebrae
Vertebrae with ribs extending ventrally and dorsally
Extend between adjacent muscle masses
Dorsal ribs well developed in pike, suckers, minnows
Vertebrae with ribs extending ventrally and dorsally
Extend between adjacent muscle masses
Dorsal ribs well developed in pike, suckers, minnows
Nice photoNice photo
Vertebrae in various fishesVertebrae in various fishes
Osteichthyes skullOsteichthyes skull
Osteichthyes skullOsteichthyes skull
>50 bones comprising 5 “groups” Neurocranium Suspensorium Jaws Opercular bones Branchiohyoid apparatus
>50 bones comprising 5 “groups” Neurocranium Suspensorium Jaws Opercular bones Branchiohyoid apparatus
NeurocraniumNeurocranium
Braincase Most of the bones Core of solid bone
around the brain plus loosely articulated bones to permit feeding (suction) and respiratory (pump) movements
Braincase Most of the bones Core of solid bone
around the brain plus loosely articulated bones to permit feeding (suction) and respiratory (pump) movements
SuspensoriumSuspensorium
Bones that connect (“suspend”) the braincase to the jaws
Bones that connect (“suspend”) the braincase to the jaws
JawsJaws
Upper and lower jaws
Change from stiff, biting mouth to flexible, sucking mouth
Maxilla (primitive), premaxilla (advanced), dentaries
Upper and lower jaws
Change from stiff, biting mouth to flexible, sucking mouth
Maxilla (primitive), premaxilla (advanced), dentaries
Opercular bonesOpercular bones
No equivalent in jawless fishes or Chondrichthyes
Primary role in respiratory pumping
Advancements (from primitive condition) small, centered on improving efficiency
No equivalent in jawless fishes or Chondrichthyes
Primary role in respiratory pumping
Advancements (from primitive condition) small, centered on improving efficiency
Branchiohyoid apparatusBranchiohyoid apparatus
Floor of the mouth, support for the gills
Includes the branchiostegal rays
Function in expansion of branchial chamber for respiration, suction feeding
Floor of the mouth, support for the gills
Includes the branchiostegal rays
Function in expansion of branchial chamber for respiration, suction feeding
Advanced fish skullAdvanced fish skull
Pectoral, pelvic girdlesPectoral, pelvic girdles
Pectoral girdlePectoral girdle
Fin rays articulate with radial bones (usually 5 radials)
Radials articulate with scapula, coracoid
These articulate with cleithrum, others
Cleithrum attached to skull
Fin rays articulate with radial bones (usually 5 radials)
Radials articulate with scapula, coracoid
These articulate with cleithrum, others
Cleithrum attached to skull
Pelvic girdlePelvic girdle
Fin rays articulate with basipterygial bone
Basipterygials either united with each other, or with cleithrum/pectoral girdle complex in more derived teleosts
Fin rays articulate with basipterygial bone
Basipterygials either united with each other, or with cleithrum/pectoral girdle complex in more derived teleosts
Dorsal, anal fin supportDorsal, anal fin support
Pterygiophores orinterspinous bones
Fish musculatureFish musculature
Segmental musclesSegmental muscles
-Right and left sidesseparated by verticalseptum-Dorsal and ventral masses separatedby horizontalseptum
Epaxial, hypaxial musclesEpaxial, hypaxial muscles
Above horizontal septum - epaxials
Below horizontal septum - hypaxials
Above horizontal septum - epaxials
Below horizontal septum - hypaxials
W-shaped myotomesW-shaped myotomes
Red vs. white musclesRed vs. white muscles
-Red - rich in blood supply - aerobic swimming (slow)-White - poor in blood supply - burst swimming (fast)-Pink - intermediate-Color may be diet-based (carotenoids/crustaceans)