Blue Marlin and Similar Species
Makaira nigricans
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Open the appSeveral fish can be confused with Blue Marlin. Here are the key differences.
Species often confused with {name}
White Marlin
Kajikia albida
Key differences: White Marlin are generally smaller, have a more rounded dorsal fin, and their pectoral fins are flexible and can be folded flat against the body. Their lateral line is a simple, single line, not reticulated. Their bill is also shorter and more slender.
Striped Marlin
Kajikia audax
Key differences: Striped Marlin (found in the Indo-Pacific) have more pronounced vertical stripes, a taller and more pointed first dorsal fin, and flexible pectoral fins. Their body is also more compressed laterally.
Black Marlin
Istiompax indica
Key differences: Black Marlin (found in the Indo-Pacific) have rigid pectoral fins that cannot be folded flat against the body, a shorter and thicker bill, and a more robust body. Their first dorsal fin is proportionally lower than the Blue Marlin's.
Swordfish
Xiphias gladius
Key differences: Swordfish have a much longer, broader, and flattened bill (sword-like), lack pelvic fins, and have a single keel on each side of the caudal peduncle (Blue Marlin have two). Their dorsal fin is also distinctly different, with a tall, crescent-shaped first dorsal and a small, separate second dorsal.
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