Blackfin Cardinalfish

Astrapogon puncticulatus

The Blackfin Cardinalfish, known scientifically as Astrapogon puncticulatus, is a small reef-associated fish found in the tropical waters of the Western Atlantic. It inhabits regions from southern Florida, USA, through the Antilles, Caribbean, and Bahamas, extending down to Brazil. Divers are most likely to encounter this species in shallow waters, as it prefers depths ranging from 0 to 8 meters. This species is often found in clear seagrass beds, particularly those dominated by Thalassia testudinum, where it typically takes shelter in empty snail shells. Blackfin Cardinalfish are mouthbrooders, with distinct pairing observed during courtship and spawning. This reproductive strategy involves one parent, usually the male, carrying the fertilized eggs in its mouth until they hatch. Such behavior is an adaptation to increase the survival rate of the offspring in the dynamic reef environment. Divers may encounter the Blackfin Cardinalfish during night dives or early morning excursions, as they are often caught during these times. The species is currently listed as Least Concern on the IUCN Red List.