The Gem Tang (Zebrasoma gemmatum) is a rare and visually stunning marine fish highly prized in the aquarium hobby. Native to the waters of the Western Indian Ocean around Madagascar and Mauritius, this species is known for its striking coloration and exclusivity. 
 
Key characteristics:
 
Appearance: Jet-black or dark brown body adorned with luminous white speckles, contrasted by a vibrant yellow tail and yellow-edged fins.
Size: Reaches up to 8-9 inches (20-23 cm) in length.
Habitat: Found in deeper coral reef environments, often in surge zones. 
 
An active herbivore, the Gem Tang thrives in large, established aquariums with plenty of live rock for grazing. While generally peaceful with other fish, it can be territorial with other tangs, requiring careful tank mate selection. Due to its limited range and collection challenges, the Gem Tang is one of the most sought-after and valuable fish for serious marine aquarists.