How large can Japanese spider crabs grow?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

crustacean The American lobster (*Homarus americanus*) is among the largest crustaceans.

The Japanese spider crab (Macrocheira kaempferi), a member of the crustacean class, is considered the largest known species within the arthropod phylum.312

These massive marine creatures can reach impressive dimensions:

Leg Span: When fully extended, their legs can span up to 3.7 to 4 meters (approximately 12 to 13 feet) from the tip of one claw to the other.312
Body Size: Despite their vast reach, the central body is relatively compact, measuring about 37 centimeters (15 inches) or roughly one foot across.31
Weight: The total body weight of a large specimen can exceed 18 kilograms (40 pounds).3

These crabs inhabit the deep Pacific waters near Japan, typically at depths ranging from 50 to 300 meters (150 to 1,000 feet), where they slowly traverse the seafloor as scavengers.31