Chocolate Surgeonfish

Purplish black in color; an orange diffused patch at edge of gill opening, just above pectoral fin base; a broad black band from upper end of gill opening to margin of gill cover down to isthmus; caudal spine socket with a narrow black margin. Blackish lips; a trace of orange behind eye; a white line under chin extending slightly above rictus. Gill rakers on anterior row 23-26; on posterior row 25-27. Juveniles can exhibit 3 different color patterns mimicking Centropyge species. Caudal fin rounded in juveniles.Description: Characterized further by having length of caudal spine about 2.5-4.5 in head lengh; greatest depth of body 1.8-2.0 in SL (Ref. 90102).

Dorsal spines (total): 8; Dorsal soft rays (total): 27 - 30; Analspines: 3; Analsoft rays: 24 - 28

Occurs in lagoon and seaward reefs; prefers areas of mixed coral, rock, or sand at the base of reefs or ledges, Ref. 48637. Also on silty reefs (Ref. 9710). Found singly (Ref. 9710). Juveniles mimic Centropyge spp. (in Guam, juveniles mimic C. flavissimus but in Palau where this species is absent, they mimic C. vrolikii), Ref. 48637. Presence of a venom gland could not be determined despite the presence of distinct anterolateral grooves; this may be due to the loss of venom glands in adults (Ref. 57406). Feeds on algae (Ref. 89972).

fisheries: commercial; aquarium: commercial

廣泛分布於印度-太平洋區，西起塞昔爾，東至馬貴斯及土木土群島，北至日本，南至澳洲大堡礁及新加勒多尼亞。台灣各地海域及離島均曾發現，以北部、東北部海域最多。

一般以流刺網、延繩釣或潛水鏢魚法等捕獲。觀賞及食用兼具。剝皮後，煮薑絲湯，肉質鮮美。尾柄上骨質盾板非常銳利，易傷人，處理時需小心。

體呈橢圓形而側扁。頭小，頭背部輪廓隨著成長而略凸出。口小，端位，上下頜各具一列扁平齒，齒固定不可動，齒緣具缺刻。背鰭及臀鰭硬棘尖銳，分別具VIII棘及III棘，各鰭條皆不延長；胸鰭近三角形；幼魚時尾鰭呈圓形，隨著成長逐漸呈彎月形，成魚時上下葉延長。幼魚體色共有3種型態：一為一致呈黃色；二為呈黃色，但鰓蓋、背鰭、臀鰭及尾鰭具藍緣，此為模仿黃尾刺尻魚(/Centropyge ferrugatus/)之體色；三為呈淡灰綠色，後部逐漸變黑色，此為模仿福氏刺尻魚(/Centropyge vrolicki/)之體色。隨著成長，體逐漸呈黃褐色，成魚呈暗褐色，體側不具任何線紋，但在胸鰭基部上下具大片橘黃色斑駁，鰓蓋後部具黑色寬斜帶。背鰭及臀鰭黑褐色，鰭緣為黑色，基底各具一黑色線紋；尾鰭黑褐色，具黃色寬線緣；胸鰭及腹鰭黑褐色；尾柄棘溝緣為黑色。

主要棲息於潟湖外側、近潮池之礁區或礁砂混合區，棲息深度一般在3-40公尺以內，最深可達60公尺。幼魚則活動於水表層至水深3公尺處。以附著藻類、矽藻或有機碎屑為食。稚魚會擬態成刺尻魚(/Centropyge/ spp)的主要原因是這些蓋刺魚科的小型魚類，生性害羞，活動很隱密，因此掠食者早已學習到不可能捕食到它們。

Acanthurus pyroferus is a species of fish in the family Acanthuridae, the unicornfishes and tangs. Its common names include chocolate surgeonfish, mimic surgeonfish, orange-gilled surgeonfish, Pacific mimic surgeon, and yellowspot surgeon.

This fish can be found in the Indo-Pacific, excluding Hawaii. It lives primarily around steep, shallow slopes near the coast with clear sand and corals. It reaches 25 centimeters in length.

This fish is occasionally kept in aquaria.

Occurs in lagoon and seaward reefs; prefers areas of mixed coral, rock, or sand at the base of reefs or ledges. Juveniles mimic @Centropyge@ spp.; in Guam, juveniles mimic @C. flavissimus@ but at Palau where this species is absent, they mimic @C. vrolikii@.