Black-Tail Dascyllus Care Guide
Dascyllus melanurus is a Western Pacific damselfish resembling D. aruanus but with a fourth black bar on the tail; territorial and aggressive with age.
Compiled by Aquairi from published sources · Published · Updated
Overview
Dascyllus melanurus is a marine damselfish of the family Pomacentridae, described by Bleeker in 1854. According to FishBase it occurs in the western Pacific from Sumatra to Vanuatu, north to the Ryukyu Islands and south to New Caledonia. It resembles the three-stripe damsel but carries an additional black bar at the tail, giving four black bands in total.
Taxonomy
- Family: Pomacentridae
- Genus: Dascyllus
- Scientific name: Dascyllus melanurus
- Author: Bleeker, 1854
Habitat
FishBase records the species from sheltered lagoons, harbours and inlets, where it associates with isolated coral heads at depths of about 1 to 68 metres. Wikipedia notes that juveniles school in groups while adults become increasingly territorial. It is a reef-associated marine fish of the western Pacific.
Tank requirements
- Minimum tank volume: 150 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Specific gravity: typical reef salinity (KB GH range 8-12)
- Size: 7-8 cm (FishBase max 8.0 cm TL)
- Lifespan: 5-10 years
Diet
The species is an omnivore. FishBase reports that it feeds on diverse plankton including larval shrimps and crabs, algae, ostracods, amphipods, pelagic tunicates, copepods and fish eggs. In aquaria a varied diet of marine frozen and planktonic foods plus prepared rations is appropriate.
Compatibility
It is a territorial damselfish that becomes more aggressive with age. Juveniles may school in groups, but adults defend territory, so robust tank mates such as tangs and wrasses suit it better than slow or shy fish. Keeping several damsels in a small tank is not recommended.
Breeding
Dascyllus melanurus is an oviparous egg-layer. FishBase reports that the eggs are demersal and adhere to the substrate, and that males guard and aerate the nest, as in related Dascyllus species.
Conservation status
IUCN Red List: Least Concern (assessed 23 September 2021). FishBase notes the species enters both commercial fisheries and the aquarium trade.
Black-Tail Dascyllus Breeding Guide
Overview
Dascyllus melanurus, the blacktail or four-stripe humbug, occurs in the Indo-Australian Archipelago and western Caroline Islands, including Indonesia, the Philippines, New Guinea and the northern Great Barrier Reef. It typically grows to about three or four inches and is patterned with three black-and-white vertical bands plus a fourth black band on the tail. It travels in schools, is omnivorous, and becomes territorial and aggressive with age. As a damselfish it spawns demersal eggs that the male guards.
Sexing
Damselfishes show little reliable external sexual dimorphism, and Chrysiptera and Dascyllus are not protandrous hermaphrodites in the clownfish sense. D. melanurus shows no clear external sexual dimorphism; in juvenile schools of up to about 25 fish, breeding pairs form within the group and the male is identified by his nest defence. In practice a compatible male/female pair is identified by behaviour once a hierarchy forms, with the dominant male defending a nest site.
Conditioning
Damsels are hardy omnivores; conditioning relies on varied feeding (frozen and prepared marine foods plus some algae) and stable reef water. Because most species are aggressive, a breeding pair is best given its own territory with ample rockwork so the male can establish and defend a nest site without constant conflict.
Breeding Setup
- Compatible established pair given its own territory
- Temperature 24-26 C, pH 8.1-8.4, stable salinity
- Hard substrate (rock, rubble or shell) for the demersal egg patch
- Plenty of rockwork and hiding places to defuse aggression
Spawning Behavior & Trigger
Spawning follows the damselfish pattern, in which the male clears and prepares a hard nest site and the female lays a patch of adhesive demersal eggs that attach to the substrate for the male to fertilise. Aggression rises with maturity, so the breeding male will vigorously defend the nest territory.
Egg & Fry Care
The male performs the parental care, guarding the nest and aerating the eggs until they hatch. Across the family Pomacentridae the eggs hatch after about two to seven days depending on species and temperature. Newly hatched larvae measure roughly 2-4 mm and enter a pelagic stage that, depending on species, can last from about a week to more than a month before the young settle and take on juvenile colours.
Common Challenges
No detailed captive-breeding account is published for D. melanurus, so husbandry follows the family pattern. The pelagic larval phase is the decisive obstacle and needs a dedicated larval system with live first foods. Increasing adult aggression also complicates keeping a stable pair with tankmates.