The Dusky Jawfish has a body that is thickly mottled with shades of dark brown and flecked with blackish spots. It is very active fish and is constantly looking for material to build up its home. The Dusky Jawfish is an amusing fish that spends all day poking its head out of its burrow and opening its wide mouth at any passing fish in an attempt to keep them away. It reaches up to 4 inches in length, is passive in nature and moderately hardy in stamina. The Dusky Jawfish needs to have a thick sand bed in the tank, since it mostly hang out and do best in the substrate and loves to dig tunnels in it. It is mostly found to be active during daytime and less at night. The Dusky Jawfish does well in groups, but can also live alone. Since there is no distinguishing feature to differentiate males from females, breeding this species is hard in captivity. The Dusky Jawfish should not be kept in a tank less than 20 gallon. It thrives well in a temperature range of 77-79 degrees Fahrenheit and pH of 8.1-8.3. If the tank parameters are maintained well, life of this fish increases that makes a long lived fish in the tank. Although it is peaceful fish and can be kept with docile fishes only, it might turn aggressive towards the same species fish in the tank. The Dusky Jawfish may eat small delicate shrimps but other than that it is considered an excellent reef safe species. It feeds on benthic and planktonic invertebrates, adapts well to frozen and even dried foods. The Dusky Jawfish should be fed at least 3 times a day for its continued good health. Being in such a petite size, it makes a good fish in smaller aquarium.