Flathead Spongegoby

Phyllogobius platycephalops

The Flathead Spongegoby is a small reef-associated goby found in the western Indian Ocean and the western Pacific Ocean, including regions like Mozambique, Indonesia, the Philippines, Solomon Islands, and the Great Barrier Reef. It inhabits coral reefs at depths ranging from 2 to 18 meters. This species is known for its commensal relationship with foliaceous flattened sponges of the genus Phyllospongia, where it often resides. This goby can be identified by its translucent body adorned with fine red or black dots and distinctive reddish markings. It has two indistinct longitudinal rows of reddish dashes on its back and a red line extending from its upper lip to its eye. Notably, it has a U-shaped reddish mark on each side of its occiput behind the eye. The Flathead Spongegoby's head is extremely flattened, and it features a rounded caudal fin, unrestricted gill openings, and unbranched lowermost pectoral rays that are thickened distally. Divers encountering the Flathead Spongegoby can expect to find it in close association with its sponge hosts, blending in with the reef environment. The species is harmless to humans and is currently classified as Least Concern by the IUCN.