Threadfin Reefgoby

Priolepis nuchifasciata

The Threadfin Reefgoby is a small reef-associated fish found primarily in the Western Pacific region, including areas from Australia and New Guinea to the Philippines and Hong Kong. It typically inhabits rocky estuary reefs, often residing in small caves and usually seen in pairs. This species is cryptic, making it a bit challenging to spot during a dive. Divers can identify it by its reddish to mauve coloration with dark scale margins that form a network pattern on its body. The head and upper back below the dorsal fin display a series of dark-edged pale grey to whitish bars, with a pair of bars forming an inverted 'Y' in front of the pectoral fin. Occasionally, individuals may have a yellow head. The Threadfin Reefgoby is non-migratory and prefers depths ranging from 5 to 30 meters. It grows to a maximum length of 4.0 cm. Despite its small size, the species has distinctive dorsal and anal fin structures, with 6 to 7 dorsal spines and 7 to 11 dorsal soft rays, along with a single anal spine and 6 to 8 anal soft rays. The fish is harmless to humans and holds a conservation status of Least Concern according to the IUCN. Encounters with the Threadfin Reefgoby can be a rewarding experience for divers who enjoy observing the subtle beauty of reef ecosystems. However, due to its cryptic nature and small size, patience and a keen eye are required to spot this elusive goby.