LiveAquaria produced and delivered, a fully conditioned specimen of the Red Sea “Harlequin” Filefish, Oxymonacanthus halli. I cook dinner for my wife and son, go run some errands, and come home to a Facebook posting from Dr. Matt Wittenrich, waving this picture of Oxymonacanthus halli from LiveAquaria on my wall, there, taunting me publicly. It’d be like, oh, what the Peppermint Angelfish is for the rest of you. Talk about a virtual smack in the face, the kind that leaves your jaw on the ground while grinning ear-to-ear. Did I mention it was already SOLD by the time I found out about it?! Someone just got really lucky.
This Red Sea version of the Longnose, aka. Orange Spot, aka. Harlequin Filefish, Oxymonacanthus longirostris, has been on my dream list ever since I succeeded in breeding and rearing O. longirostris. But honestly, I had written this fish off as one of those Fisheous unobtaniatumi (or something like that) – Kevin Kohen’s name for the whack hole-in-the-wall type marine fish species that the everyday aquarist isn’t even aware they exist (eg. Synchiropus circularis).
In every sense of the word, I had written O. halli off as a fish I’d dream about, but would never see. Not many people have ever kept this species in captivity, but we can presume that it is a SPS feeder much like the sister species O. longirostris. Thus, probably everything written on the subject of care for the Harlequin Filefish is probably applicable to the Red Sea Harlequin Filefish. Steve Krogh, Operations Manager at the Rhinelander facility (Diver’s Den & the Coral Farm) confirms that Oxymonacanthus halli appears to behave the same, and require the same husbandry as O. longirostris.
They allow only passive fish for tankmates, and by the time the fish are ready for sale, they are trained to eat enriched Brine Shrimp and Mysis, as well as Nutramar Ova. Based on that information, this is definitely a species I would recommend only for people who will either let it graze their SPS tank, or otherwise give it very specific customized care that Oxymonacanthus filefish require. And even then, I might go so far as to say that really, only those who’ve kept the regular Harlequin Filefish successfully, should be jumping on the bandwagon to snap up this exceptionally rare-in-the-trade species.