Fish biology and anatomy (2) Flashcards
Fish Dissection
Lay fish on right side (To show all internal organs)
Open the body cavity with three cuts
A) 1st line originated from cranial to anus and run cranial till point ventral to operculum
B) 2nd line from the same point cranial to anus and run cranial through dorsum of body cavity till point dorsal to operculum
C) 3rd line connects the 1st line with 2nd line
1st line
From cranial to anus and run cranial till point ventral to operculum
2nd line
from the same point cranial to anus and run cranial through dorsum of body cavity till point dorsal to operculum
3rd line
connects the 1st line with 2nd line
Fusiform shape
Streamlined , oval body shape
Tuna
Typical fast swimming in open water
Compressiform shape
Laterally compressed (flat from side to side)
Tilapia
Quick bursts of speed over short distances
Depressiform shape
Flattened top to bottom
Sole fish , skates and rays
Flap fins up and down and swim like a bird
Filliform shape
Snake like swimming movement
Pipefish , Sand eel
Their long body allow them to move into narrow opening and resist the force of water current
Anguilliform shape
Snake like swimming movement
Eels
Their long body allow them to move into narrow opening and resist the force of water current
FINS are supported by
Rays which are connected to musculoskeletal system
Fin rays types
Soft
Flexible , jointed
Spine
Stiff , a jointed , mineralized
Fins types “as numbers”
Paired fins
Pectoral , pelvic
Unpaired fins
Dorsal ,caudal and anal
Dorsal fin
- located on back of fish ,it supported with spines
- Its use for rapid change of direction, stabilization and braking
Single fin covering whole fish dorsum
Cichlidae family as Oreochromus niloticus
Single small part fin of fish back
Cyprinidae family as Silver carp - Mirror carp
Dorsal fin divided into 2 part
one is anterior (Spiny) and posterior (Soft) as Family Mugilidae (cephalus - capito)
Salmon Dorsal fin
Dorsal fin is soft rayed & there are adipose flab near tail fin
In catfish dorsal fin is
absent and is replaced by rayless adipose flab
Caudal fin
- Usually soft ray
- Used for locomotion mainly (propelling of fish through water) Its shape vary with motion type used by different species
Caudal fin shapes
Crescent or lunate
Forked
Round or truncated
Eel like shape
Crescent or lunate
Very fast speed over very long distances
Tuna fish
Forked “Caudal fin”
Fast speed over long distance
Mugilidae
Round or truncated “Caudal fin”
Give quick burst (Fast swimming for short distance)
Guppy fish
Eel like shape “Caudal fin”
Dorsal, Anal and Caudal fins fused with each other forming single fin for movement in narrow opening
Anguilla fish
