The Grey Knight Goby
inhabits tidal river estuaries, mangrove and the lower reaches of freshwater
It is benthic in habits, sometimes occurring in water just a few centimetres
deep. It is carnivorous, and feeds on fish fry, aquatic invertebrates and
Identifying features include the black spots on the flanks, which are
arranged in broken rows parallel to the body, and the long first dorsal fin,
which has a black blotch at the base. The second dorsal fin is shorter, but
the first the anal fin is well
developed, and the tail fin is relatively large and rounded. All fins,
except the first dorsal fin, are speckled to some degree.
The species ranges from coastal areas of Pakistan eastwards through the
Indian subcontinent and Sri Lanka. In Southeast Asia it occurs in the
western half including Burma, Thailand, Cambodia, Peninsular Malaysia
and Singapore. In Indonesia it occurs in coastal areas of Sumatra.
Fig 1 : Grey Knight Goby, in full sunlight, in the lowermost stretch of
a freshwater stream flowing into Burau Bay, Langkawi, Peninsular Malaysia.
Fig 2 : Habitat of the Grey Knight Goby at Burau Bay - a shallow, rocky
freshwater stream with sandy substrate.
Fig 3 : Specimen from Pulau Semakau, a partly mangrove-fringed island off
Fig 4 : Mangrove habitat at Pulau Semakau, Singapore.
Order : Perciformes
Family : GOBIIDAE
Species : Stigmatogobius sadanundio
Maximum Length : To at least 6.2 cm, possibly to 9.0 cm
References : F1, F2