Description

Body design 

This is a small goby around 8 cm long. It is pale brown with a series of black target-like circles along the body just below the mid-lateral line. The foremost of these is more prominent but in appropriate light all are surrounded by iridescent blue spots. The background colour of the body below the mid-lateral line is dark brown. Running vertically down from the fore and aft edges of the white outlines of the ‘targets’ are white lines that reach the ventral surface. 

Above the mid-lateral line, the base colour is a lighter brown. It is crossed by conspicuous white bars, the one at the level of the pectoral fins being the most conspicuous. 

The head is paler than the rest of the body. The cheek is pale with brown spots behind the eye coalescing and becoming fine dark bars on the gill cover. The nostrils are elongated and tubular

Fin design 

The first dorsal fin is triangular, transparent with alternating spots of brown and white on the fin rays. The second dorsal fin is rectangular and similarly patterned. The pectoral fin has its origin in a brown-spotted white area lying behind the gill cleft. it is transparent. The pelvic fins have a bright white base and are then vertically barred in brown and white. The anal fin is rectangular with vertical brown and white bars. The caudal fin is transparent with fine brown flecks on the fin rays. 

Diagnostic features

The white dorsal bars and the white-outlined black targets are the best identification features. 

Similar species

Several gobies of this genus have a similar look but this is the most widespread and is the one you usually find in the patch reefs and overhangs. 

The main similar species to consider are 

C leucostictus and C maudae which do not have the row of ‘targets’. 

Cryptocentrus nigrocellatus, the Blackspot Shrimpgoby has a single ocellated spot just in front of the pectoral fin. 

Cryptocentrus caeruleomaculatus has more conspicuous iridescent blue spots and less contrasting head markings.