Morphology Data of Oncorhynchus mykiss
Identification keys
Abnormalities
Main Ref. Hart, J.L., 1973
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features none
Body shape lateral fusiform / normal
Cross section compressed
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

Body elongate, somewhat compressed especially in larger fish. No nuptial tubercles but minor changes to head, mouth and color occur especially in spawning males. Coloration varies with habitat, size, and sexual condition. Stream residents and spawners darker, colors more intense. Lake residents lighter, brighter, and more silvery. Caudal fin with 19 rays (Ref. 2196). Differs from Oncorhynchus gorbuscha by having the following unique characters: by having the following unique characters: anal fin with 6-9½ (usually 8½ ) branched rays; 115-130 scales in midlateral row; 16-17 gill rakers; breeding males lacking hump; juveniles lacking parr marks; wide pink to red stripe from head to caudal base, except in sea-run form; and juveniles with 5-10 parr marks (Ref. 59043).

Ease of Identification

Meristic characteristics of Oncorhynchus mykiss

Lateral Lines Interrupted: No
Scales on lateral line 135 - 150
Pored lateral line scales 100 - 150
Scales in lateral series
Scale rows above lateral line 22 - 26
Scale rows below lateral line 23 - 30
Scales around caudal peduncle
Barbels
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total 15 - 22
Vertebrae
preanal
total 60 - 66

Fins

Dorsal fin(s)

Attributes no striking attributes
Fins number 1
Finlets No. Dorsal   0 - 0
Ventral  0 - 0
Spines total 0 - 0
Soft-rays total 10 - 12
Adipose fin present

Caudal fin

Attributes more or less truncate; more or less normal

Anal fin(s)

Fins number 1
Spines total 0 - 0
Soft-rays total 8 - 12

Paired fins

Pectoral Attributes  more or less normal
Spines     1
Soft-rays   11 - 17
Pelvics Attributes  more or less normal
Position    abdominal  behind origin of D1
Spines     2
Soft-rays   8 - 10
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Entered by Garilao, Cristina V.
Modified by Torres, Armi G.
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