Pinecone fishesMonocentridae

Pinecone fishes (Monocentridae) are small, compact marine fishes with distinctive heavily armoured bodies, typically growing up to 15 cm (6 in). Their deep, oval-shaped bodies are covered in large, stiff, spiny scales that give them a rugged texture, resembling a pinecone, from which they derive their common name. Most species display yellow to orange-brown colouration, often with dark margins on each scale. A prominent pair of bioluminescent organs is located on their lower jaw.

These organs house symbiotic bacteria that produce a glow, used by the fish to attract prey in dark environments. Pinecone fishes are primarily nocturnal, feeding on small crustaceans. They inhabit deeper reef slopes, caves, and crevices, typically below 20 m (65 ft) and reaching depths of 200 m (650 ft). Generally cryptic, they are infrequently encountered by divers due to their preference for deep, nocturnal habitats.