International Commission for the Conservation of Atlantic Tunas

SHEET 1: TECHNICAL TERMS AND SPECIES IDENTIFICATIONWAHOO - (Acanthocybium)

1st dorsal ﬁn (spines)

2nd dorsal ﬁn (soft rays)
Caudal keels
Interdorsal space

Adipose eyelids

Dorsal ﬁnlets

HeightHead length

BaseAnal ﬁnlets
Corselet

Fork length

1. WAH - Wahoo (Acanthocybium solandri)
Geographical distribution: Entire Atlantic Ocean

1st dorsal ﬁn (24 to 26 spines)

2nd dorsal ﬁn and anal ﬁnfollowed by 8 to 9 ﬁnlets

Snout as long as the restof the headNumerous dark vertical shaded lines on theﬂanks just below the lateral line

Author: Taïb Diouf. Fisheries Biologist. Dakar, Senegal

SHEET 2: SPECIES IDENTIFICATION
MACKERELS – (Scomberomorus)
1. MAW- West African Spanish mackerel(Scomberomorus tritor)
Geographical distribution: East Atlantic coast(from the Canary Islands to Angola)

2. KGM- King mackerel(Scomberomorus cavalla)
Geographical distribution: West Atlantic coast(from the United States to Brazil)

Front part of the 1stdorsal (black colour)

No colour on the1st dorsal
Two dorsal ﬁns with narrow spaceTwo dorsal ﬁns with narrow space

2nd dorsal ﬁn followed by 9 spines
Snout much shorter than
the rest of the head

Back part of the jawbone exposed

Second anal ﬁn followed by 7 to 9spines (in general 8 spines)

Lateral line progressively
drops after the 2nd dorsal ﬁn

Back part of the jawbone exposed

Lateral line with a sharp drop at
the level of the 2nd dorsal ﬁnSilvery side with no marks

3. SSM- Spanish mackerel (Scomberomorus maculatus)
Geographical distribution: West Atlantic (North of Belize)
Black area on the ﬁrst
part of the ﬁrst dorsal ﬁn

Two dorsal ﬁns
with narrow space

Back part of the jawbone exposed

4. CER- Cero mackerel(Scomberomorus regalis)
Geographical distribution: West Atlantic

1st dorsal ﬁn of 16 to 18 spines
stFront part of the 1
dorsal ﬁn is blackand posterior partis white

Grey side with a discontinousline in the middle

2nd dorsal ﬁn of 16 to 19
spines followed by 7 to
9 ﬁnlets

Lateral line progressively
dropping until the caudal ﬁnSilvery sides with approximately threerows of rounded or elliptical dark spots

5. BRS- Serra Spanish mackerel(Scomberomorus brasiliensis)
Geographical distribution: West Atlantic(South of Belize)

Black 1st dorsal ﬁn
Snout much shorter than
the rest of the head

Pelvic ﬁn relatively short

Lateral line progressively
curving to the lower area,
towards the caudal peduncle

Pectoral ﬁns without scales
except towards the lower area

SHEET 3: SPECIES IDENTIFICATIONSMALL TUNAS – (Euthynnus, Auxis, Sarda, Katsuwonus)
1. LTA- Little tunny(Euthynnus alletteratus)
Geographical distribution: Entire Atlantic Ocean

2. FRI- Frigate tuna(Auxis thazard)
Geographical distribution: Entire Atlantic Ocean

2 dorsal ﬁns separated by a narrow spaceFirst part of the spinesof the dorsal ﬁn are
taller than thoselocated in the middle

2 dorsal ﬁns
completely separated

2nd dorsal ﬁn a lot lower
than the ﬁrst andfollowed by 8 ﬁnlets

3 to 8 shaded marks
under pectoral ﬁn
Short pectoral ﬁns

Strong central keel on each sideof the caudal peduncle between
two smaller keels

Very thin caudalpeduncle

Anal ﬁn followed by 7 ﬁnlets

Short pectoral ﬁn reaching towards
the back until the begining of thesmooth part above the corselet

15 small shaded wavy, obliques orpractically horizontal stripes orlines above the lateral line

3. BLT- Bullet tuna (Auxis rochei)
Geographical distribution: Entire Atlantic Ocean
Two dorsal ﬁns completely separated
Black mark on the posterior
ventral rim of the eye

Short pectoral ﬁn that does not reachthe origin of the smooth area above
the corselet

4. BON- Atlantic bonito(Sarda sarda)
Geographical distribution: Entire Atlantic OceanLong 1st dorsal ﬁn, practicallyreaching the 2nd dorsal ﬁn

At least 15 dark lines, wideand practically vertical,
above the lateral line

Strong central keel in eachside of the caudal peduncle,
between 2 smaller keels

5. SKJ- Skipjack(Katsuwonus pelamis)
Geographical distribution: Entire Atlantic Ocean

5 to 11 oblique stripes on the back and sides

Thin caudal peduncle, with a welldeveloped lateral keel locatedbetween 2 smaller keels

3 to 6 very visible longitudinal shaded stripes on the stomach

Juveniles of large tunas can be mis-identiﬁed as small tunas – please pay attention to descriptions of juveniles of large tuna in the next sheet

SHEET 4: SPECIES IDENTIFICATIONLARGE TUNAS – (Thunnus, Orcynopsis)
1. YFT- Yellowﬁn(Thunnus albacares) - Juvenile
Geographical distribution: Entire Atlantic Ocean

Pectoral ﬁns reachthe beginning of the2nd dorsal ﬁnRounded extremeties in pectoral ﬁns

2. BET- Bigeye(Thunnus obesus) - Juvenile
Geographical distribution: Entire Atlantic Ocean

Pectoral ﬁns exceeding
the begininning of the 2nddorsal ﬁn
Pointed extremity of pectoral ﬁns

Slender body particularly
near the caudal ﬁn

Potbellied bodyLines slightly curved, regularlyspaced out, separated by marks
forming lines throughout practically the entire body

3. ALB- Albacore (Thunnus alalunga) - Juvenile
Geographical distribution: Entire Atlantic OceanFirst dorsal ﬁn slightly higher
than the second

Back part of the caudal
ﬁn white or transparent

Practically strait lines, irregularly spaced out, with some irregular marks,
especially on the lower part of the body

4. BFT- Blueﬁn (Thunnus thynnus thynnus) - Juvenile
Geographical distribution: North Atlantic
1st dorsal ﬁn including 12 to 14 spines

2nd dorsal ﬁn is higher than the ﬁrst

Semi-transparent
caudal keel
(adults - black)Very short pectoral ﬁns
Sides and ﬂanks are silvery white withtransparent transversal lines alternatingwith transparent dotted lines

Pectoral ﬁns greatly extends past the second
dorsal ﬁn and the anal ﬁn

5. BLF- Blackﬁn tuna(Thunnus atlanticus) - Adult
Geographical distribution: West Atlantic

6. BOP- Plain bonito(Orcynopsis unicolor) - Adult
Geographical distribution: East Atlantic

Short 1st dorsal ﬁn, tall and bonyspines (12 to 14 spines)

Large eyes

2nd dorsal ﬁn followed by
7 to 9 ﬁnlets

Short head withpointed snout

Oblique mouth and paranasal jaw start at thevertical of the centre of
the eyeSlightly long pectoral ﬁns,
above the begininning of
the dorsal ﬁnVery large mouth withupper jaw reaching theback edge of the eye

Pronounced and slightly
winding lateral line
Short pectoral ﬁn with 21 to 23 rays

Anal ﬁn followedby 5 to 8 ﬁnlets