Spotted Boxfish

Family: Boxfishes (Ostraciidae)
Size: 15 – 25 cm (6 – 10 in) | Weight: ~180g
Depth: 3 – 30m (10 – 100ft)
Distribution: Tropical Indo-Pacific and Eastern Pacific Ocean.

Identification:
A fish with two faces. This species displays extreme sexual dimorphism, meaning males and females look completely different.

• Females & Juveniles: They have a box-shaped body that is dark brown or black, covered entirely in small white spots. This pattern helps them blend into the shadows of the reef.
• Adult Males: They transform into a vibrant blue color with bright orange bands and spots on the sides. This coloration advertises their toxicity to predators.
• Shape: Unlike most fish, they have a rigid, hexagonal bony carapace (exoskeleton) that acts like armor, leaving only their fins, eyes, and mouth free to move.

Behavior:
A shy but toxic swimmer.

• Defense: They are poor swimmers due to their rigid bodies. To compensate, they have a chemical defense mechanism: when stressed or threatened, they can release a toxic slime (ostracitoxin) from their skin that repels predators.
• Reproduction: Males are territorial and usually keep a "harem" of several females within their territory. Spawning occurs at dusk, where the pair rises several meters above the reef to release eggs.