1. MORPHOLOGY

2. INTRODUCTION
Separating a family taxon, genus taxon in addition to their use in identifying species taxon
The nature of adipose eyelids- Carangidae
Develop in posterior half of eye-Alepes, Selaroides
Completely covering eye except vertical slit- Atule-Selar
Well developed – Caranx tille
Its development
Extension of maxillae, Thryssa setirostris very long
Thryssa mystax small reach pectoral fin
Short in Stolephorus
Position of nostrils

3. Nature of operculum whether serrated or not, -Serranidae, with spine Scorpaenidae, Platycephalidae
Presence of pores around the mouth region – Sciaenidae
Barbels, its numbers,-Catfishes, Cyprinidae, Loach, Mullidae
Type of mouth-
The arching of lateral line- no-continuous-
dorsal side alone-
ventral side alone-curvature- Not full – till the end of caudal fin

4. Naked area of breast region- Carangoides
Scales in pre operculum -Nemipteridae, operculum- Lutjanidae
Head- Gerres , Myripristis
Groove in the belly-Atropus
Body shape-flat –eel like-spindle shaped-torpedo shaped
Head lizard like-lizard fish
Lower jaw elongated-half beak- Hemirampus
Two jaw elongated-Strongylura - needle fish
Upper jaw elongated- Makaaira, Istiophorus
Mouth tube like-Syngnathidae, Aulostomidae (trumpet fishes)-Fistularia

5. Colour pattern in most of the fishes changes after death
Bands on the body, the spots and pigmentation have to be studied only in fresh specimens.

6. Sometimes a morphological character attributed by a taxonomist as valid one for a species at a given length, may prove to be invalid at larger length groups or at smaller length groups
Mouth parrot like –Scaridae
Sucking disc on head-Remora
Pigments,
Bands on the lateral side, etc., - studied different length groups.

7. SCUTES Ventral scutes separate Stolephorus, Thryssa and Thryssina.
If scutes between pectoral and pelvic fins Stolephorus.
not present before the pectoral, Thryssina
Present before and behind pelvic fin, such species are placed under the genus, Thryssa and Setipinna.
Thryssa have the first pectoral fin ray normal,, Setipinna, the first ray is filamentous.
Pointed tip-conger eel- Uroconger, Trichiurus
Forked- Dolphin fish
Truncate- Aethaloperca

8. HEAD REGION

9. TYPES OF MOUTH

10. TYPES OF TEETH

11. ADIPOSE FIN AND FINLETS

12. Single large fin-Coryphaenidae-dolphin fish, Istiophoridae –Sailfish
Gill membranous unit at isthumus-Pampus
Pelvic fin absent Parastromateus , eels, Sygnathidae
Large dorsal and anal- Platax
Pectoral enlarged- Exocetus
A filametous extension in C middle -Fistularia

13. TYPES OF CAUDAL FINS

14. SNOUT ARRANGEMENTS A. Snout tip pointed B. Snout tip rounded
C. Snout tip tubular
D. Snout overhanging the mouth
E. Lower jaw projecting beyond upper jaw
F. Jaws and lips terminal
G. Upper jaw prolonged into a sword like bear
H. Upper jaw overhanging the lower jaw
Ia. Vomerine teeth
Ib. Branchiostegal rays

15. THANK YOU