Spotted Frillgoby

The Spotted Frillgoby, known scientifically as Bathygobius cyclopterus, is a small tropical fish inhabiting marine and brackish waters. Typically found near reefs, its habitat extends from intertidal seaward reef flats to shallow reefs near shore, existing at depths ranging from 1 to 20 meters (3 to 65 feet). This species is prevalent in the Indo-Pacific region, including areas from East Africa to 🇼🇸 Samoa and the Hawaiian Islands.

The Spotted Frillgoby reaches a maximum length of about 7.5 centimeters (2.9 inches). It features distinct brown coloring with irregular spots, with females displaying bands on their dorsal and caudal fins, while males have dusky fins. A notable characteristic is the dark brown saddle marking located under each of the dorsal fins. The fish's dorsal fins consist of 7 spines and 9 soft rays, while the anal fin contains 1 spine and 8 soft rays.

Its anatomical features include upper pectoral fin rays with free tips, a partly free sixth ray, and three branches on the upper four pectoral rays. The caudal fin is rounded, and the longitudinal scale count is 37-38. Predorsal scales number between 18-20, nearly reaching the space between the eyes. The Spotted Frillgoby does not have scales on its cheeks or opercles but does have a fleshy double flap extending from the edge of its cheek into a notch at the posterior end of the upper lip.

The body of this fish is covered with ctenoid scales, transitioning to cycloid on the abdomen, breast, base of the pectoral fin, and nape. The head is notably depressed, making its width greater than its depth. The body depth measures between 4.3 and 5.5 times in the standard length of the fish. The Spotted Frillgoby is a benthic spawner, meaning it lays its eggs on the sea bed.

The genus name "Bathygobius" combines Greek and Latin, where "bathys" means deep and "gobius" translates to gudgeon, a type of small fish.