Sangihe Dwarf Kingfisher Ceyx sangirensis: a distinct and extinct endemic species

Adolf Meyer, first author of the name of the dwarf kingfisher Ceyx sangirensis, never visited the island of Sangihe, north of Sulawesi, on which he and co-author Wiglesworth stated the two syntypes were collected (by hired hunters) in the 1870s. The form was lumped with Sulawesi Dwarf Kingfisher Ceyx fallax in 1945 and split again only in 2014, based on characters shown by two other specimens Meyer had sent to the UK. However, because (a) the species was (apparently) not seen again after Meyer's birds were collected in 1874 and (b) Meyer wrote elsewhere that the original labels of some of his Sulawesi material were lost, it was recently suggested that C. sangirensis did not originate on the island. Two further specimens have come to light (including one apparently taken in 1876, thus not by Meyer's collectors) and, although one syntype has been destroyed, the total of birds conforming to key diagnostic features and labelled from Sangihe is now six. This evidence combined with other information indicates that C. sangirensis is or was indeed endemic to Sangihe, and comparisons with 39 C. fallax confirm that it should be treated as a separate species, distinguished by its longer bill and tail, more extensive blue-spangled black crown, few or no shining pale turquoise lower dorsal feathers, more mauve or magenta wash dorsally with cobalt- or royal-blue on the uppertail-coverts, and less extensive white throat. A review of field work, including three months by one of us in remaining forest on the island in 2015, shows that the species has not definitively been seen since the 1870s and must regrettably be regarded as extinct.