Explore 51 Fish That Start with U (Common Names)

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.

#1 Uaru

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.

#14 Unicornfish

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.

1. Upper Zambezi yellowfish
2. Uruguayan eartheater
3. Utah Lake sculpin
4. U-spot wrasse
5. Unicorn crestfish
6. Unicorn leatherjacket
7. Unarmored threespine stickleback
8. Umatilla dace
9. Umpqua chub
10. Umpqua dace
11. Umpqua squawfish
12. Unarmed dwarf monocle bream
13. Unicolor moray
14. United-lip gudgeon
15. Uncinate sculpin
16. Upjaw barb
17. Upper Grijalva livebearer
18. Upper Zambezi labeo
19. Upper Zambezi squeaker
20. Uruguay river sprat
21. Uncombed blenny
22. Undistinguished sabretooth
23. Unicorn grenadier
24. Unicorn icefish
25. Unicorn sole
26. Uruguay tetra
27. Union snook
28. Upside-down goby
29. Upside-down harptail blenny
30. Upturned snout rattail
31. Usumacinta buffalo
32. Usangu lampeye
33. Ussuri catfish
34. Ussuri sharpbelly
35. Usumacinta cichlid
36. Usumacinta sea catfish
37. Utah chub

Conclusion

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

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.