";} } ?> Morphology Summary - Isistius brasiliensis
Morphology Data of Isistius brasiliensis
Identification keys
Main Ref. Bass, A.J., L.J.V. Compagno and P.C. Heemstra, 1986
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral elongated
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales placoid scales

The cookiecutter shark Isistius brasiliensis is distinctive for the prominent dark collar marking around its throat, large nearly symmetrical caudal fin with a long ventral lobe over 2/3 length of dorsal caudal margin, and moderately large lower teeth in 25-32 rows. Eyes set anterior of head but sufficiently far back to lack an extensive anterior binocular field. Pectoral fins subquadrate; pelvic fins larger than dorsal fins (Ref.247). Tooth count: 30-37/25-31. Vertebral count: 81-89. Spiral valve count: 8-10 (Ref. 48844). Dark brown dorsally, paler ventrally except for blackish band across throat; tips of caudal lobe blackish (Ref. 6577). As with the other member of the genus Isistius , it has a characteristic small cigar-shaped body with two small close-set spineless dorsal fins far posterior on back, no anal fin, huge, triangular-cusped teeth without blades, short, bulbous snout and a unique suctorial lips (Ref. 247).

Ease of Identification easy to distinguish from other species.

Meristic characteristics of Isistius brasiliensis

Lateral Lines 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
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total 81 - 89


Dorsal fin(s)

Fins number 2
Finlets No. Dorsal   0 - 0
Ventral  0 - 0
Spines total 0 - 0
Soft-rays total 0 - 0
Adipose fin absent

Caudal fin

Attributes other (see remark); asymmetric

Anal fin(s)

Fins number
Spines total 0 - 0
Soft-rays total 0 - 0

Paired fins

Pectoral Attributes  more or less normal
Spines     0
Soft-rays   0 - 0
Pelvics Attributes  more or less normal
Position    abdominal  behind origin of D1
Spines     0
Soft-rays   0 - 0
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
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