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Common Name/s: Threespot / Flagfin Angelfish
Maximum Adult Size: 26cm
Natural Distribution: Indo-West Pacific: East Africa south to 28°S and east to Samoa, north to southern Japan, south to Australia.
Depth Range: 3 – 60m
Species Notes & Captive Care Notes: This species inhabits lagoons and seaward reef habitats such as steep reef slopes and drop-offs. It has also been observed around lagoon pinnacles and patch reefs in quite shallow water. It is typically found near areas of significant coral coverage and feeds mainly on sponges and tunicates as an adult. Juveniles are more secretive and occur below 25m, feeding mainly on algae. Adults frequently occur in small but loose, haremic groups at moderate depths. Care requirements are typical of the Apolemichthys genus but using quality live ocean rock for the building of the reefscape is recommended for this species as it is known to be a fussy eater that can prove difficult to settle and transition onto prepared foods. The naturally occurring grazing that live rock provides is therefore very important. Specimens in the 5 to 10cm range are reputed to stand the best chance of settling into captive life while very small, or large specimens often fail to adapt. Compared to other members of the genus, A. trimaculatus often proves to be peaceful but can also be quite shy, and likely to be intimidated by all but the most benign of tankmates, particularly when small. Juveniles have a small black spot on rear of dorsal, while adults have a small streamer on the upper lobe of the caudal fin. Having a range that overlaps with a number of other Apolemichthys species, the flagfin angel is known to hybridise fairly regularly and examples of crosses with A. xanthurus are well-known (indeed for a time such crosses were designated as a species in their own right, A. armitagei). Beyond this, as well as successfully captive-breeding purebloods of the sepcies, Bali Aquarich crossed this species with A. xanthopunctatus in 2015. Captive-bred specimens do crop up from time-to-time in the trade and are a much better proposition that wild-caught individuals. An interesting aberrant specimen which exhibited possible partial axanthism was captured in June 2019.
References / Further Reading:
ReefBuilders “First of its Kind Aberrant Flagfin Angelfish Discovered in Philippines”
IUCN page with zoomable range map
Large adult shown below (note upper tail streamer)
Sub adult shown below
Juvenile shown below (note black spot on dorsal)