Oxymonacanthus longirostris

Datasheet

General Description

The Harlequin filefish (Oxymonacanthus longirostris) belongs to the Monacanthidae family and can reach a maximum size of 12.0cm. This species, also known as the Longnose filefish, Longnosed filefish, Coral filefish, or Beaked leatherjacket, is found in the Indo-Pacific region from East Africa to Samoa and south to the southern Great Barrier Reef. They are distinct in appearance and some individuals might find their unique look appealing.

Aquarium Suitability

Aquarists considering the Harlequin filefish for their tanks should exercise caution and be well-prepared due to specific demands this species has. They might be challenging to maintain in captivity as they primarily feed on coral polyps. It is essential to be prepared to provide alternative food sources as they may not readily adapt to new diets. Althoug, it is crucial to note that there is a high percentage of these fish that may not survive long in captivity, even with the appropriate care.

Demands, Care, and Hardiness

Harlequin filefish are not recommended for reef tanks as they have a diet that can pose challenges to maintain coral populations. They require shelters and hiding spots within the aquarium, preferring to stay between live rocks. When introducing them to a new tank, they might exhibit shyness initially and prefer peaceful surroundings. Special care is needed when catching them as they can easily get caught in nets. These fish are considered average in hardiness and require a minimum tank size of 400 liters.

Reef Suitability

The Harlequin filefish is not reef-safe due to its diet primarily consisting of coral polyps. They are not suitable for coral tanks and might pose a threat to the coral and invertebrate populations within the reef aquarium setup.

Aquarium Setup

For a successful aquarium setup for Harlequin filefish, ensure there are ample hiding spaces, such as live rocks. These fish need room for swimming, so a spacious tank is recommended. Maintaining stable water conditions with a temperature range of 22.2-25.6°C, pH of 8.1-8.4, and specific gravity of 1.020-1.025 is crucial for their well-being.

Behaviour

This species is mostly peaceful but can display aggression towards similar species. They can live in pairs, consisting of a male and a female. Harlequin filefish might show shyness at first, especially in new environments, but can become more active and social once acclimated.

Feeding and Diet

The recommended diet for Harlequin filefish includes small polyp stone corals (SPS). Providing alternative food sources is vital for their survival in captivity, as they may not readily accept new food types. Live acropora can be used initially to sustain them while transitioning to other food options.

Dimorphism

No specific information provided.

Habitat and Distribution

In the wild, Harlequin filefish are found in the East Indian Ocean, West Indian Ocean, Australia, Japan, Indonesia, and the Central/West Pacific region. Their distribution ranges from East Africa to Maputo, Mozambique, east to Samoa, north to the Ryukyu Islands, and south to the southern Great Barrier Reef, New Caledonia, and Tonga. These fish are replaced by Oxymonacanthus halli in the Red Sea.