Morphology Data of Thunnus albacares
Identification keys
Abnormalities
Main Ref. Collette, B.B., 2001
Appearance refers to
Bones in OsteoBase Skull, Spine

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features striking fins
Body shape lateral fusiform / normal
Cross section oval
Dorsal head profile more or less straight
Type of eyes more or less normal
Type of mouth/snout more or less normal
Position of mouth terminal
Type of scales
Diagnosis

This large species is distinguished by the following characters: elongate, fusiform body, slightly compressed laterally; total gill rakers on first gill arch 26-34; dorsal fins 2 and separated only by a narrow interspace, the second followed by 8-10 finlets; anal fin followed by 7 to 10 finlets; large specimens may have very long second dorsal and anal fins, becoming well over 20% of fork length; pectoral fins moderately long, usually reaching beyond second dorsal-fin origin but not beyond end of its base, usually 22-31% of FL; 2 flaps (interpelvic process) between pelvic fins; body with very small scales; corselet of larger scales developed but not very distinct; caudal peduncle very slender, bearing on each side a strong lateral keel between 2 smaller keels; no striations on ventral surface of liver; swimbladder present. Colour of back metallic dark blue changing through yellow to silver on belly; belly frequently crossed by about 20 broken, nearly vertical lines; dorsal and anal fins, and dorsal and anal finlets bright yellow, the finlets with a narrow black border (Ref. 9684).

Ease of Identification

Meristic characteristics of Thunnus albacares

Lateral Lines 1 Interrupted: No
Scales on lateral line
Pored lateral line scales
Scales in lateral series
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Barbels 0
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total 26 - 34
Vertebrae
preanal
total 39

Fins

Dorsal fin(s)

Attributes other
Fins number 2
Finlets No. Dorsal   8 - 10
Ventral  7 - 10
Spines total 11 - 14
Soft-rays total 12 - 16
Adipose fin absent

Caudal fin

Attributes forked; more or less normal

Anal fin(s)

Fins number 1
Spines total 0 - 0
Soft-rays total 11 - 16

Paired fins

Pectoral Attributes  rays very elongated
Spines     0
Soft-rays   30 - 36
Pelvics Attributes  more or less normal
Position    thoracic  before origin of D1
Spines     
Soft-rays   
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Entered by Reyes, Rodolfo B.
Modified by Capuli, Estelita Emily
Comments & Corrections
Sign our Guest Book
Back to Search
cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17