Allen's Cardinalfish

Cheilodipterus alleni

Allen's Cardinalfish is a reef-associated species found in the Western Central Pacific, specifically around Papua New Guinea, Flores in Indonesia, and Sibvan Island in Borneo. It inhabits seaward reef slopes at depths ranging from 10 to 40 meters. This fish is recognized by its pale body adorned with eight golden brown stripes. The stripes below the middle of the body are equal to or slightly wider than the spaces between them, while those above are slightly narrower. The first dorsal fin is distinctly marked with a black distal half and a pale proximal half, while the other fins have a reddish tinge, with the leading edges of the second dorsal and anal fins appearing dusky to dark brown. Allen's Cardinalfish is typically solitary, often found in caves and under ledges. It exhibits mouthbrooding behavior, with distinct pairing during courtship and spawning. The smallest mature female of this species measures 6.3 cm in length, while the maximum length recorded is 10.4 cm. Despite its specific habitat preferences, Allen's Cardinalfish is currently assessed as Least Concern on the IUCN Red List. Divers encountering this species can expect to find it hiding in crevices or sheltered areas of the reef. Its cryptic behavior and preference for shaded environments make it a subtle presence on the reef, adding to the diversity of marine life observed during dives.