Pyramid Butterflyfish, Hemitaurichthys polylepis
Image Caption: Pyramid Butterflyfish in Kona, Hawaii. Credit: AquaImages/Wikipedia (CC BY-SA 2.5)
The pyramid butterflyfish is found in tropical waters in the Eastern Indian Ocean, Western Pacific, South-east Asia, Japan, Australia, around the Great Barrier Reef, and Hawaiian Islands. This species often swims in large schools from just below the surface to 130 feet in depth, around steep outer reef slopes.
The pyramid butterflyfish has a white pyramid shaped patch on each side of the body. The young will have a yellow head, but will gradually change to brown as it ages. The average length is around 7 inches long, having 12 dorsal spines with 23 – 26 soft rays, and 3 anal spines with 19 – 21 soft rays.
If kept as a pet in an aquarium, 100 gallon or larger tank is recommended, with at least 4 other specimens of the same species. Pyramid butterflyfish have been known to survive in captivity for up to 12 years.
External fertilization is done in pairs with no distinct difference between the male and female of this species.