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Common Name: Regal (Blue) Tang

Scientific Name: Paracanthurus hepatus


Kingdom: Animalia

Phylum: Chordata

Class: Osteichthyes

Order: Perciformes

Family: Acanthuridae

Genus: Paracanthurus

Species: P. Hepatus


Which animal is the Paracanthurus hepatus? Well, Paracanthurus hepatus is the fish named “Dory” in the movie Finding Nemo. The kingdom, phylum, class, order, family, genus, and species are listed in order: Animalia, Chordata, Actinopterygii, Perciformes, Acanthuridae, Paracanthurus, and Paracanthurus hepatus. In the genus of Paracanthurus, this is the only species. The common names are: Regal (Blue) Tang, Surgeonfish, Flagtail Surgeonfish, Hippo Tang, and Palette Tang. The habitat of this tang is in either the ocean (they are saltwater fish) or in a saltwater tank. In the ocean, they are usually located in mainly several areas: Indo-West Pacific, Great Barrier Reef, Queensland, and around East Africa to the Line Islands.


In the aquarium, they are usually very aggressive to other tangs. They grow to about twelve inches in the wild, but only around six inches if kept in an aquarium. In the aquarium, the Regal Tang likes high oxygen gas concentration. If you want to have a Blue Tang in an aquarium, make sure the other tangs, large basses, angelfish, and triggerfish do not annoy your tang too much or the Regal Tang will stop eating. They like a lot of motion in the water, so the more turbulent the water, the better. The Regal Tang is very active (look in the movie Finding Nemo), curious, anxious eaters, and they like to sample food.


In the wild, the Regal Tang is an omnivore/herbivore. The Regal Tang usually eats zooplankton, small plants, and algae. Zooplanktons are small animals like tiny shrimp and other tiny organisms. Algae are small, eukaryotic organisms that range from single-celled organisms to large multi-cellular organisms. The predators of the Regal Tang are bigger fish. They include sharks, barracudas, and fish that are hungry enough to try to capture this active fish. Most fish, however, are warned away because of the yellow triangular spot of color on the Regal Tang’s tail. The yellow is a warning coloration that the tail has spines.


Reproduction is very hard in captivity. When they do reproduce, however, they swim up a little bit from the bottom of whatever place they are reproducing in and lay their eggs. The eggs float to the bottom of whatever place they are reproducing in and lay their eggs. The eggs float to the bottom, and they mature from the embryos there. The baby fish that hatch from the eggs are yellow (most of the time).


The class distinction is mainly two things. All of the fish in the class Actinopterygii have a pair of fins that are supported by slender rays of bone. They are known as ray-finned fishes. Some of the fishes located in the class of the ray-finned fishes are the world’s fastest swimmers. A pike can swim as fast as one of the fastest human runners can run, around 48 kilometers per hour. The Regal Tang has three main distinctions from the class and family. The family is Acanthuridae, and the differences from the class and the family are the spines, fins, and mouth. The spines are on either sides of the tail, and they are sharp enough to cause injury to those who do not know of it. The fins are very large dorsal and anal fins. They extend to most of the length of the body.


The mouth has a single row of teeth that are used for grazing on algae. The Regal Tang has a very brilliant yellow triangle starting at the base of the tail to across the tail fin. It is because when the Regal Tangs were younger, they were all yellow until they matured. It has a bright blue body, and has a black band “covering” the fish’s eye that controls the dorsal half of each side of the body. Within the band, there is a circular blue area. The pectoral fins are semi-transparent to transparent yellow. The edges of the dorsal and anal fins are black.


Surgeonfish have a small spine that is located on the two sides at the base of the tail. The spines flick outwards against the skin of the animal grabbing its tail. The yellow triangle on the tail is a warning to its predators and enemies that it has poisonous spines located in the tail. That is an example of warning coloration. The economic and social importance of the Regal Tang is that it is prey to other animals, and predator to other food items. They are also a good pet, and a great friend. If you are hungry enough, they could also become our food.


In the movie Finding Nemo, it shows that “Dory” (who is a Regal Tang, that’s why I picked the Regal Tang) is very fast when she was racing Marlin (the clownfish) through the Jellyfish Forest. She said, “You can’t beat evolution. I was built for speed.” It shows that Regal Tangs are curious because when Marlin and Dory just swam over the trench, while Marlin was looking the other way and complaining about Dory being wrong, Dory met a small jellyfish and called him “Squishy.” I picked Paracanthurus hepatus as my animal because of one main reason: I like Dory. In the movie Finding Nemo, Dory is a very energetic fish who has short-term memory loss. She meets Marlin while Marlin was looking for his lost son, Nemo. Dory is like me in one way because she always confuses Nemo’s name to something else, like Harpo, Chico, and Elmo. I confuse my nieces’ and nephews’ names all the time. Dory is a cool fish, the best fish there is (at least to me), and so I picked the Paracanthurus hepatus as my animal to do research on.


Author: Emily T.  

Published: April 2006


Allen, Katy Z. et al. Life Science. Austin: Holt, Rinehart, and Winston Company, 2001. Angelfire.

 "Regal Tang.", date unknown.

 Dale, Jim. "Reefing the Australian Way." Reefing the Australian Way. Nov. 2004. MASA. Knopf, Alfred A.

 Eyewitness Books: Fish. New York: Toppan Printing Co. (S) Pte Ltd, 1990. Spider, The. "Aquarium of the Bay.", 1996-2001, specific date unknown. Unknown. "EPA- Current State Biological Assessment Programs." Coral Reef Fish - Surgeonfishes. 01 Mar. 2006. Biological Indicators of Watershed Health. White, John. "Animal Pictures Archive: Animal Photo Album." Animal Photo Album. 02 Dec. 2005. Wikipedia. "Acanthuridae.", 2006.

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