Morphology Data of Thunnus alalunga
Identification keys
Abnormalities
Main Ref. Collette, B.B. and C.E. Nauen, 1983
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs no special organs
Different appearance males alike females
Different colors males alike females
Remarks

Descriptive characteristics of juvenile and adult

Striking features none
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

Anterior spines much higher than posterior spines giving the fin a strongly concave outline. Interpelvic process small and bifid. Body with very small scales. Pectoral fins remarkably long, about 30% of fork length or longer in 50 cm or longer fish. Ventral surface of liver striated and the central lobe is largest.

Ease of Identification

Meristic characteristics of Thunnus alalunga

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 24 - 31
Vertebrae
preanal
total

Fins

Dorsal fin(s)

Attributes no striking attributes
Fins number 2
Finlets No. Dorsal   7 - 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  more or less normal
Spines     0
Soft-rays   30 - 36
Pelvics Attributes  more or less normal
Position    thoracic  before origin of D1
Spines     
Soft-rays   
Back to Search
Comments & Corrections
cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17