Yellowhead Jawfish
Opistognathus aurifrons
Also known as: Jack in the box, Jack In The Box
A sand-burrowing fish that hovers upright and broods eggs in its mouth.
About
The yellowhead jawfish (Opistognathus aurifrons) is one of those fish that immediately draws attention not for flashy coloration but for genuinely odd behavior. Its body is pale with a soft yellow wash over the head and face, and it spends most of its time hovering nearly upright just above the burrow it has excavated from crushed coral or sandy substrate. That burrow is everything to this fish. It retreats into it headfirst when threatened, which is where the old nickname 'jack in the box' comes from. Native to the warm shallow waters of the western Atlantic, from southern Florida and the Bahamas down to northern South America, it tends to occur in colonies where individuals maintain their own burrows without actively defending territory against neighbors. Pairs are monogamous, and courtship involves the male swimming in a curved posture with fins fanned out. Perhaps most remarkably, the male carries and incubates the eggs in his mouth until they hatch. In the aquarium this species needs a deep sand bed to construct a proper burrow, and a tight-fitting lid is essential since these fish are surprisingly capable jumpers. With those needs met, it is a rewarding and personable fish for an intermediate keeper.
Similar species
Other fish you might consider
Good tank mates
Species that tend to coexist peacefully with Yellowhead Jawfish
From the same region
Share the same natural habitat. Great for a biotope-themed tank
Frequently asked questions
- How big does the Yellowhead Jawfish get?
- The Yellowhead Jawfish reaches about 2.5–4" as an adult.
- What size tank does the Yellowhead Jawfish need?
- A minimum of 20 gallons is recommended for the Yellowhead Jawfish.
- What water parameters does the Yellowhead Jawfish need?
- The Yellowhead Jawfish does best with a temperature of 72–82°F, a pH of 8.1–8.4.
- Is the Yellowhead Jawfish aggressive?
- The Yellowhead Jawfish is generally peaceful and suits a community tank with similarly calm tankmates.
- What does the Yellowhead Jawfish eat?
- The Yellowhead Jawfish is a carnivore. It needs a meaty, protein-rich diet of frozen or live foods.
- How long does the Yellowhead Jawfish live?
- With good care, the Yellowhead Jawfish typically lives 5-8 years.
- Is the Yellowhead Jawfish reef safe?
- The Yellowhead Jawfish is generally considered reef safe.