Grey shrimpgoby freckled with small blue spots, common on silty sand near the reef edge.
A stout shrimpgoby to about 13 cm, grey to olive-brown with several broad darker saddles along the back and the whole head and body sprinkled with small pale blue spots. The blue spotting extends onto the cheek and the fins, and is the mark that carries it. The yellow shrimpgoby Cryptocentrus cinctus is the species most often confused with it: that fish is either plain bright yellow or plain grey with only faint blue flecks concentrated on the head, is smaller, and lacks the strong dark saddles. Mahidolia mystacina is smaller again and raises a first dorsal fin far taller than the body.
Occupies a burrow dug and kept open by an alpheid snapping shrimp. The shrimp does the excavation, shovelling sediment out with its claws in short trips, and stays in touch with the goby through one long antenna; the goby faces out of the entrance and signals danger by moving, which sends both animals below. Feeds on small crustaceans and on invertebrates picked from the sediment surface.
Recorded from about 3 to 25 m and one of the more tolerant shrimpgobies of fine silty bottoms, so it turns up well away from coral on open muck slopes as well as at the reef edge. Large individuals sit high on the fins with the mouth slightly open and hold position longer than the small species do.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
