Juvenile Black Snapper, Apsilus dentatus (Lutjanidae), Mimic Blue Chromis, Chromis cyanea (Pomacentridae)
Young Black Snapper, Apsilus dentatus (Lutjanidae), were observed to mimic Blue Chromis, Chromis cyanea (Pomacentridae), in the Cayman Islands. The behavior may explain its juvenile coloration and depth preference. The mimicry probably has not been previously recognized because of the rarity of A. dentatus at scuba diving depths. The geographic ranges of the black snapper (insular West Indies) and the other known blue-chromis mimic, the Blue Hamlet, Hypoplectrus gemma (Serranidae, Florida, Belize), are mutually exclusive. Only three snapper species are known mimics, all of Chromis spp. Multiple-species mimicry of the same model species is uncommon in fishes, and this is the first record of such for the Atlantic.Abstract
A juvenile black snapper, Apsilus dentatus, (Lutjanidae) photographed by LB-W on the outer reef slope at 27 m depth off Little Cayman, Cayman Islands, 80°05.1′W, 19°40.9′N, 3 August 1998
Map of the Cayman Islands with filled circles designating survey sites with black grouper mimics and open circles those without; stippled areas represent land; scale bar between islands = 10 km; scale bar within islands = 1 km; cross = 19°30′N, 80°W. (A) Position of all three islands, left to right (west to east), Grand Cayman, Little Cayman, Cayman Brac. (B) Grand Cayman. (C) Little Cayman. (D) Cayman Brac