Common Name: Orangefin Skunk Anemonefish
Scientific Name: Amphiprion sandaracinos Allen 1972
Distribution: Coral Triangle, north through the Ryukyu Arc, south into the Rowley Shoals
Type Locality: Pagbilao Island, Luzon Island, Philippines
Identification: A thick white stripe extending along the back from the upper lip to the base of the caudal fin; this stripe is noticeably thicker than in the related perideraion group. Fins tinged orange, rather than the translucent white typically seen in the perideraion group. Relatively large size, up to 13.5 mm.
Similar: Similar to A. akallopisos, A. cf akallopisos and A. pacificus, all of the perideraion group. The fin color, dorsal stripe shape and host selection allow for easy identification. Still, this is one of the most frequently misidentified species of Amphiprion, with many of the internet images identified as this fish being incorrect.
Notes: The Coral Triangle distribution of this species is unique within the genus, and it’s interesting to note how this fish has failed to cross into the Eastern Indian Ocean while all other major lineages have. Genetic studies have thus far presented a muddied view of this fish’s evolutionary history, offering what is almost certainly spurious support for a close relationship with the Pacific Ocean taxa of the perideraion group. This might be indicative of some amount of introgression between the two resulting from the rare instance of hybridization. It is exceedingly rare for these to be spotted in the same anemone, and it remains to be seen what a hybrid would look like.
In all likelihood, this unique fish is the sole member of its own highly distinct branch in the anemonefish evolutionary tree, sister to the diverse perideraion group, which speciated thanks to a specialization in Stichodactyla carpet anemones. Interestingly, there is little indication of any regional diversification across its widespread range in the West Pacific. No doubt, genetic data will reveal some cryptic population structure in accord with what is seen elsewhere in the genus.
Known to interbreed with A. cf chrysopterus in New Guinea and the Solomon Islands, resulting in a variably patterned hybrid that has been incorrectly classified as A. leucokranos, the White-bonnet Anemonefish.