From crabs to lobsters and seahorses to humpback whales, under the ocean, there are a host of many living creatures. Among those creatures that inhabit the seas are fish. According to the National Oceanic and Atmospheric Association (NOAA), there are more than 20,000 species of living fish that exist underneath our waters. It’s hard to keep track of the number, especially if you want to alphabetize them!
Let’s explore 51 fish that start with the letter U and highlight some of the most popular and common ones, in no particular order.
The uaru is a weird-looking, triangle-shaped fish. Uaru means toad in the Amazonian language. The fish lives in the Orinoco and Amazon rivers of South America. They are usually not the most colorful and vibrant of aquarium fish, but they have become popular over time. The uaru are also intelligent fish that feed off crustaceans, worms, and insects.
#2 Uganda Nothobranch
This species of fish resides in Kenya and Uganda. It’s a freshwater fish that is small and known for its bright colors, usually red or blue. The most fascinating thing about these colorful fish, though, is that you can sometimes find them in pools, drainage areas, and swamps.
#3 Ukrainian Brook Lamprey
This fish is a species of lamprey that lives mainly in the Balkan region of Europe, as well as Eastern Europe. Specifically, you can find the Ukrainian brook lamprey in the mountainous regions of these countries in fresh bodies of water. This long fish is usually prey for other larger fish.
#4 Umbrella Cichlid
Found in rivers in South America, the umbrella cichlid is a small, colorful, yellow fish. They usually eat insects and crustaceans and when they breed, it’s usually because of the excess of water from the heavy rains.
#5 Umbrella Conger
The umbrella conger resides at the sandy bottom of the Pacific Ocean, usually near Australia, Papua New Guinea, and New Zealand. It’s a long fish that can grow up to 17 inches in length, which makes it look like an eel.
#6 Underjaw Kingfish
The underjaw kingfish, which has several other names, makes its home in tropical or warm regions of oceans. Specifically, it lives in the Pacific, Atlantic, and Indian Oceans. It has a metallic green color, with its fins a yellowish color. Interestingly enough, if you are an avid fisherman, the underjaw kingfish makes for good food. But beware, they are good fighters!
#7 U-Mark Sandperch
The U-mark sandperch generally calls home areas around Southern Japan and Australia, near Queensland. They inhabit lagoons and their food consists of smaller fish and invertebrates. Although they are colorful and attractive to humans, they are not considered fish for consumption.
#8 Undulate Painted Ray
This species of ray primarily lives in the Mediterranean Sea, but you may also find it in the North Atlantic near Ireland and England and all the way to South Africa. Because of its popularity in fishing, the IUCN lists this species as ‘endangered.’
#9 Undulated Moray
Found in the Indo-Pacific region of the seas, the undulated moray is a species of eel that has colorful yellow, green scales. A nocturnal fish that hides around reefs, they can move back and forth. Hawaiian folklore has attributed this moray as a protector of families, usually ancestors coming back as these fish.
#10 Ulrey’s Tetra
This is a very colorful fish that is common to find in aquariums across the world. Originally from Paraguayan waters, the Ulrey’s tetra is a small fish that loves hot temperatures.
#11 Upland Bully
This freshwater fish calls the waters of New Zealand home. A dull brown, yellow color, the upland bully has small orange spots across its body. They are also very small fish that grow to only three inches. Believe it or not, even though the name may suggest it, the upland bully is not a bully at all.
#12 Upside-Down Catfish
The upside-down catfish is a freshwater fish that got its name from the fact that, curiously, it feeds more easily when it’s upside down. It dwells in rivers that have a lot of vegetation. The upside-down catfish is gray-brown in color, but sometimes it can switch into an invertebrate to trick prey or escape from predators.
#13 Urchin Clingfish
Let’s start off by stating the obvious. This is a very weird-looking fish. The urchin clingfish can only grow to about two inches. It has a very elongated body with dark red scales and three yellow lines along its body. They are tropical fish, usually found in the Indo-Pacific region of the world.
We come to a very colorful and interesting-looking fish on our list. Unicornfish prefer to hide out in coral reefs. The horn between the eyes of this fish gives it its name. They are colorful-looking fish of blue and green (sometimes silver too) found near coral reefs in the Pacific and Indian Oceans.
#15 The Largest Fish That Starts with U — The Utah Sucker
Now, let’s discuss the largest fish that starts with the letter U. That prize goes to the Utah sucker. The Utah sucker is a freshwater fish that mainly lives in the Snake River and post-Lake Bonneville areas in the United States. It can grow from 15 to a whopping 25 inches in length. Having a mixture of colors, the Utah sucker has been in decline in recent years due to habitat destruction along the river. An article in the American Fisheries Society Symposium stated that habitat recovery and conservation efforts are critical for the Utah sucker to survive.
Other Fish That Start with the Letter U
Of course, those aren’t the only fish in the world that start with U. We list others below.
- Upper Zambezi yellowfish
- Uruguayan eartheater
- Utah Lake sculpin
- U-spot wrasse
- Unicorn crestfish
- Unicorn leatherjacket
- Unarmored threespine stickleback
- Umatilla dace
- Umpqua chub
- Umpqua dace
- Umpqua squawfish
- Unarmed dwarf monocle bream
- Unicolor moray
- United-lip gudgeon
- Uncinate sculpin
- Upjaw barb
- Upper Grijalva livebearer
- Upper Zambezi labeo
- Upper Zambezi squeaker
- Uruguay river sprat
- Uncombed blenny
- Undistinguished sabretooth
- Unicorn grenadier
- Unicorn icefish
- Unicorn sole
- Uruguay tetra
- Union snook
- Upside-down goby
- Upside-down harptail blenny
- Upturned snout rattail
- Usumacinta buffalo
- Usangu lampeye
- Ussuri catfish
- Ussuri sharpbelly
- Usumacinta cichlid
- Usumacinta sea catfish
- Utah chub
And there you have it, a total of 51 fish that start with the letter U. Some of them have hard-to-pronounce names while others have funny names. Some of them are named after people and others after countries. All of these fish are unique, which contribute to the ecosystem in a positive way.
Summary of Fish That Start with the Letter U
Fish with Common Names That Start with the Letter U
|Common Fish Name||Scientific Name|
|Uganda nothobranch||Nothobranchius ugandensis|
|Ukrainian brook lamprey||Eudontomyzon mariae|
|Umbrella cichlid||Apistogramma borellii|
|Umbrella conger||Gnathophis umbrellabius|
|Underjaw kingfish||Pseudocaranx dentex|
|U-mark sandperch||Parapercis snyderi|
|Undulate painted ray||Raja undulata|
|Undulated moray||Gymnothorax undulatus|
|Ulrey’s tetra||Hemigrammus ulreyi|
|Upland bully||Gobiomorphus breviceps|
|Upside-down catfish||Synodontis nigriventris|
|Urchin clingfish||Diademichthys lineatus|
|Upper Zambezi yellowfish||Labeobarbus codringtonii|
|Uruguayan eartheater||Gymnogeophagus australis|
|Utah Lake sculpin||Cottus echinatus|
|U-spot wrasse||Halichoeres stigmaticusis|
|Unicorn crestfish||Eumecichthys fiski|
|Unicorn leatherjacket||Aluterus monoceros|
|Unarmored threespine stickleback||Gasterosteus aculeatus|
|Umatilla dace||Rhinichthys umatilla|
|Umpqua chub||Oregonichthys kalawatseti|
|Umpqua dace||Rhinichthys evermanni|
|Umpqua squawfish||Ptychocheilus umpquae|
|Unarmed dwarf monocle bream||Parascolopsis inermis|
|Unicolor moray||Echidna unicolor|
|United-lip gudgeon||Platysmacheilus longibarbatus|
|Uncinate sculpin||Icelus uncinalis|
|Upjaw barb||Coptostomabarbus wittei|
|Upper Grijalva livebearer||Poeciliopsis hnilickai|
|Upper Zambezi labeo||Labeo lunatus|
|Upper Zambezi squeaker||Synodontis woosnami|
|Uruguay river sprat||Ramnogaster melanostoma|
|Uncombed blenny||Haptoclinus apectolophus|
|Undistinguished sabretooth||Odontostomops normalops|
|Unicorn grenadier||Coelorinchus productus|
|Unicorn icefish||Channichthys rhinoceratus|
|Unicorn sole||Aesopia cornuta|
|Uruguay tetra||Cheirodon interruptus|
|Union snook||Centropomus unionensis|
|Upside-down goby||Trimma striatum|
|Upside-down harptail blenny||Meiacanthus abditus|
|Upturned snout rattail||Coelorinchus mycterismus|
|Usamacinta buffalo||Ictiobus meridionalis|
|Usangu lampeye||Lacustricola usanguensis|
|Ussuri catfish||Pseudobagrus ussuriensis|
|Ussuri sharpbelly||Hemiculter lucidus|
|Usumacinta cichlid||Kihnichthys ufermanni|
|Usumacinta sea catfish||Potamarius usumacintae|
|Utah chub||Gila atraria|
Fish with Scientific Names That Start with the Letter U
Some fish have scientific names that start with the letter U. We’ve listed those below.
|Fish with Scientific Names Starting with U|
|Umbrina milliae (common name: Miller drum)|
|Ungusurculus williamsi (common name: Williams’ viviparous brotula)|
|Uranoscopus guttatus (common name: Dollfus’ stargazer)|
The photo featured at the top of this post is © chonlasub woravichan/Shutterstock.com
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