These three angelfishes form an unexpected clade within the phylogeny of Pomacanthidae. Note the placement of narcosis’ spot versus arcuatus’ stripe and colini’s back. Photo credit: Lemon TYK.
In gross review of the vast piscine fauna distributed around the globe, there are perhaps few families of fish that can rival the unparalleled beauty and elegance that comes with the marine angelfishes of the family Pomacanthidae. Their painterly brilliance, comical personalities and intelligent nature have secured their iconic position amongst a buzzing plethora of reef denizens in which they share their aquatic home with. Needless to say, their captivating and inviting qualities have piqued the interest of naturalists and aquarists alike, seeking to appreciate their beauty both in the field, as well as in the home aquaria. But, while angelfish in general are fabulously well known and studied (you’ll be hard pressed to find a new species these days!), their systematic classifications have mostly been in disarray. In the grand scheme of bony fish evolution, we know that angelfishes are a relatively recent arrival, having separated from a common ancestor with the butterflyfishes (Chaetodontidae) around 52 million years ago (MYA). During this time, the larger angelfish species were the first to diverge, forming what we now know today as Holacanthus, Pomacanthus and Chaetodontplus. The dwarf angelfishes only diverged much later, sharing a common ancestor with Pygoplites around 30-33 MYA. While Pygoplites superficially resemble very little to the modern day dwarf angelfish, its predilection for crypsis and a generally cloistered lifestyle hints at a slight likeness to those of Centropyge. Recent molecular studies have elucidated the long awaited phylogeny of angelfishes, in particular, shedding light on the more taxonomically speciose Centropyge.
A partial phylogeny of modern day angelfishes, based on research conducted by Gaither et al., 2014. Note that Genicanthus and Apolemichthys are nestled within the paraphyletic Centropyge. Photo credit: Lemon TYK.
A recent phylogenetic study conducted by Gaither et al., reveals Centropyge to be paraphyletic. In addition, Genicanthus and Apolemichthys are found to be nestled deep within the dwarf angelfish tree, sharing a common ancestor with many of these “Centropyge” groups. More surprising, however, is the discovery of a sister clade comprising three unlikely species – one of which hardly comes to mind when pondering the intricacies of Centropyge. They are Centropyge colini, narcosis and Apolemichthys arcuatus.… More:
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