There are 301 fish that start with the letter U, from Uaru to Uwakita. Below you will find them listed alphabetically along with some general information about each. Click the toggle view buttons in the top right corner to switch between the card and the table view.
For each item you will find the following information
Order: The subclass the fish belongs to
Habitat: The places or type of weather the fish lives in
Scientific name: The designation that scientists use to catalog the species
Name: Uaru
Order: Cichliformes
Habitat: Freshwater
Scientific name: Uaru amphiacanthoides
Name: Uaru cichlid
Order: Cichliformes
Habitat: Freshwater (Amazon Basin)
Scientific name: Uaru amphiacanthoides
Name: Uaru-tucuxi
Order: Cichliformes
Habitat: Freshwater
Scientific name: Symphysodon sp. 'tucuxi'
Name: Ubiquitous Gourami
Order: Anabantiformes
Habitat: Southeast Asia
Scientific name: Trichopsis vittata
Name: Uca
Order: Gobiiformes
Habitat: Brackish
Scientific name: Uca pugnax
Name: Uca annulipes
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca annulipes
Name: Uca argus
Order: Decapoda
Habitat: Brackish (East Atlantic estuaries)
Scientific name: Uca argus
Name: Uca borealis
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca borealis
Name: Uca coarctata
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca coarctata
Name: Uca crassipes
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca crassipes
Name: Uca dussumieri
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca dussumieri
Name: Uca elegans
Order: Decapoda
Habitat: Brackish (East Pacific estuaries)
Scientific name: Uca elegans
Name: Uca flammula
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca flammula
Name: Uca forcipata
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca forcipata
Name: Uca lactea
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca lactea
Name: Uca longirostris
Order: Decapoda
Habitat: Brackish (East Pacific estuaries)
Scientific name: Uca longirostris
Name: Uca princeps
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca princeps
Name: Uca pugilator
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca pugilator
Name: Uca pugnax
Order: Decapoda
Habitat: Brackish (Western Atlantic estuaries)
Scientific name: Uca pugnax
Name: Uca rapax
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca rapax
Name: Uca speciosa
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca speciosa
Name: Uca tangeri
Order: Decapoda
Habitat: Marine/Brackish
Scientific name: Uca tangeri
Name: Uca triangularis
Order: Decapoda
Habitat: Brackish (Indo-Pacific estuaries)
Scientific name: Uca triangularis
Name: Udara
Order: Perciformes
Habitat: Marine
Scientific name: Udara dussumieri
Name: Uechi
Order: Perciformes
Habitat: Marine
Scientific name: Uechi notatus
Name: Ugandian Lungfish
Order: Ceratodontiformes
Habitat: Freshwater
Scientific name: Protopterus aethiopicus
Name: Ugobrasse
Order: Perciformes
Habitat: Marine (South Atlantic)
Scientific name: Acanthistius brasilianus
Name: Uhde's Parrotfish
Order: Perciformes
Habitat: Marine
Scientific name: Scarus coeruleus
Name: Ula
Order: Perciformes
Habitat: Marine
Scientific name: Ula hypseloptera
Name: Ulah
Order: Siluriformes
Habitat: Freshwater
Scientific name: Ulah microphthalmus
Name: Ulcerfish
Order: Perciformes
Habitat: Marine
Scientific name: Ulcerfish anomala
Name: Ulua
Order: Carangiformes
Habitat: Marine
Scientific name: Ulua mentalis
Name: Ulupora
Order: Perciformes
Habitat: Marine
Scientific name: Ulupora bimaculata
Name: Ulupora brachycentra
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Ulupora brachycentra
Name: Ulupora macrolepis
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Ulupora macrolepis
Name: Uluulu
Order: Perciformes
Habitat: Marine
Scientific name: Uluulu akule
Name: Ulva Sea Bream
Order: Spariformes
Habitat: Marine
Scientific name: Boops boops
Name: Ulzana
Order: Perciformes
Habitat: Freshwater/Brackish
Scientific name: Ambassis urotaenia
Name: Uma
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Uma umbra
Name: Umaki
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Umaki bicolor
Name: Umbeli
Order: Perciformes
Habitat: Marine
Scientific name: Umbeli unicolor
Name: Umbellow
Order: Perciformes
Habitat: Marine
Scientific name: Dasyatis pastinaca
Name: Umbili
Order: Perciformes
Habitat: Marine
Scientific name: Umbili punctata
Name: Umbra
Order: Esociformes
Habitat: Freshwaters of Europe
Scientific name: Umbra krameri
Name: Umbraculum
Order: Perciformes
Habitat: Marine
Scientific name: Umbraculum sinense
Name: Umbramina
Order: Perciformes
Habitat: Marine
Scientific name: Umbramina striata
Name: Umbramora
Order: Gadiformes
Habitat: Marine
Scientific name: Umbramora jacksoni
Name: Umbrella Anthias
Order: Perciformes
Habitat: Marine
Scientific name: Anthias squamipinnis
Name: Umbrella Guppy
Order: Cyprinodontiformes
Habitat: Freshwater
Scientific name: Poecilia reticulata (Umbrella variety)
Name: Umbrella Mouth Catfish
Order: Siluriformes
Habitat: Freshwater
Scientific name: Phreatobius cisternarum
Name: Umbrella Squid
Order: Teuthida
Habitat: Marine
Scientific name: Graneledone boreopacifica
Name: Umbrella characin
Order: Characiformes
Habitat: Freshwater (South America)
Scientific name: Triportheus angulatus
Name: Umbrellafish
Order: Batrachoidiformes
Habitat: Marine (Western Atlantic)
Scientific name: Opsanus beta
Name: Umbrina
Order: Perciformes
Habitat: Coastal waters of the Atlantic and Mediterranean
Scientific name: Umbrina cirrosa
Name: Umbrina analis
Order: Perciformes
Habitat: Eastern Atlantic
Scientific name: Umbrina analis
Name: Umbrina broussonnetii
Order: Perciformes
Habitat: Eastern Atlantic
Scientific name: Umbrina broussonnetii
Name: Umbrina canariensis
Order: Perciformes
Habitat: Eastern Atlantic, Mediterranean
Scientific name: Umbrina canariensis
Name: Umbrina coroides
Order: Perciformes
Habitat: Western Atlantic
Scientific name: Umbrina coroides
Name: Umbrina galapagorum
Order: Perciformes
Habitat: Eastern Pacific, Galapagos Islands
Scientific name: Umbrina galapagorum
Name: Umbrina imberbis
Order: Perciformes
Habitat: Marine (East Pacific)
Scientific name: Umbrina imberbis
Name: Umbrina milliae
Order: Perciformes
Habitat: Marine
Scientific name: Umbrina milliae
Name: Umbrina musae
Order: Perciformes
Habitat: Marine
Scientific name: Umbrina musae
Name: Umbrina reedi
Order: Perciformes
Habitat: Marine (East Pacific)
Scientific name: Umbrina reedi
Name: Umbrina richardi
Order: Perciformes
Habitat: Marine
Scientific name: Umbrina richardi
Name: Umbrina robusta
Order: Perciformes
Habitat: Eastern Atlantic
Scientific name: Umbrina robusta
Name: Umbrina roncador
Order: Perciformes
Habitat: Eastern Pacific
Scientific name: Umbrina roncador
Name: Umbrina ronchus
Order: Perciformes
Habitat: Marine
Scientific name: Umbrina ronchus
Name: Umbrina steindachneri
Order: Perciformes
Habitat: Eastern Pacific
Scientific name: Umbrina steindachneri
Name: Umbrina xanti
Order: Perciformes
Habitat: Marine (East Pacific)
Scientific name: Umbrina xanti
Name: Umeboshi
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Umeboshi lunulata
Name: Unakagin
Order: Anguilliformes
Habitat: Marine
Scientific name: Unakagin nigromarginata
Name: Unati
Order: Characiformes
Habitat: Freshwater
Scientific name: Unati pinnata
Name: Unbanded Goatfish
Order: Perciformes
Habitat: Marine
Scientific name: Upeneus sulphureus
Name: Uncia
Order: Siluriformes
Habitat: Freshwater
Scientific name: Uncia fasciolata
Name: Undertakerfish
Order: Lophiiformes
Habitat: Marine
Scientific name: Undertakerfish lugubris
Name: Unicorn Anchovy
Order: Clupeiformes
Habitat: Marine
Scientific name: Setipinna taty
Name: Unicorn Blenny
Order: Blenniiformes
Habitat: Marine
Scientific name: Meiacanthus kamoharai
Name: Unicorn Fish
Order: Acanthuriformes
Habitat: Tropical and subtropical Indo-Pacific
Scientific name: Naso unicornis
Name: Unicorn Leatherjacket
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Aluterus monoceros
Name: Unicorn Surgeonfish
Order: Perciformes
Habitat: Marine
Scientific name: Naso unicornis
Name: Unicorn Triggerfish
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Balistapus undulatus
Name: Unicorn Wrasse
Order: Labriformes
Habitat: Marine
Scientific name: Hemigymnus fasciatus
Name: Unicorn filefish
Order: Tetraodontiformes
Habitat: Marine (Tropical/Subtropical worldwide)
Scientific name: Aluterus monoceros
Name: Unicorn leatherjacket
Order: Tetraodontiformes
Habitat: Marine (Tropical/Subtropical worldwide)
Scientific name: Aluterus monoceros
Name: Unicorn tang
Order: Acanthuriformes
Habitat: Marine (Indo-Pacific)
Scientific name: Naso unicornis
Name: Unicornfish
Order: Myctophiformes
Habitat: Marine (Deep sea)
Scientific name: Macrostoma mirabilis
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Name: Unidentified Anglerfish (U-species)
Order: Lophiiformes
Habitat: Marine (Deep-sea)
Scientific name: Various unknown species
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Name: Unidentified Cichlid (U-species)
Order: Cichliformes
Habitat: Freshwater
Scientific name: Various unknown species
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Name: Unidentified Eel (U-species)
Order: Anguilliformes
Habitat: Marine
Scientific name: Various unknown species
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Name: Unidentified Goby (U-species)
Order: Gobiiformes
Habitat: Marine/Freshwater
Scientific name: Various unknown species
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Name: Unidentified Hake (U-species)
Order: Gadiformes
Habitat: Marine
Scientific name: Various unknown species
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Name: Unidentified Moray Eel (U-species)
Order: Anguilliformes
Habitat: Marine
Scientific name: Gymnothorax undulatus
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Name: Unidentified Rockfish (U-species)
Order: Scorpaeniformes
Habitat: Marine
Scientific name: Various unknown species
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Name: Unidentified Shark (U-species)
Order: Selachimorpha
Habitat: Marine
Scientific name: Various unknown species
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Name: Unidentified Skark (U-species)
Order: Rajiformes
Habitat: Marine
Scientific name: Various unknown species
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Name: Unidentified Snapper (U-species)
Order: Perciformes
Habitat: Marine
Scientific name: Lutjanus sp.
Name: Unilocular
Order: Perciformes
Habitat: Marine
Scientific name: Unilocular maculatus
Name: Unio
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Unio pictorum
Name: Uniped fish
Order: Siluriformes
Habitat: Freshwater (Somalia; cave dweller) – *Note: Often used in context of having only one pair of fins.*
Scientific name: Phreatichthys andersoni
Name: Unipedal fish
Order: Tetraodontiformes
Habitat: Freshwater of Southeast Asia (a common name for some puffers)
Scientific name: Tetraodon fluviatilis
Name: Unique cichlid
Order: Cichliformes
Habitat: Freshwater (Lake Tanganyika)
Scientific name: Lamprologus ornatipinnis
Name: Uniramia
Order: Perciformes
Habitat: Marine
Scientific name: Uniramia viridis
Name: Unka
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Unka barbata
Name: Unkaria
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Unkaria robusta
Name: Unknown cichlid
Order: Cichliformes
Habitat: Freshwater (Lake Tanganyika)
Scientific name: Trematocara macrostoma
Name: Unkus
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Unkus fuscus
Name: Unpaved Scad
Order: Carangiformes
Habitat: Marine
Scientific name: Decapterus macarellus
Name: Unspotted Catshark
Order: Carcharhiniformes
Habitat: Marine
Scientific name: Atelomycterus macleayi
Name: Unspotted Flounder
Order: Pleuronectiformes
Habitat: Marine
Scientific name: Pseudorhombus arsius
Name: Unspotted Grunt
Order: Perciformes
Habitat: Marine
Scientific name: Pomadasys commersonnii
Name: Unspotted Puffer
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Arothron nigropunctatus
Name: Unspotted Stingray
Order: Myliobatiformes
Habitat: Marine
Scientific name: Neotrygon kuhlii
Name: Unspotted Triggerfish
Order: Tetraodontiformes
Habitat: Marine
Scientific name: Balistes capriscus
Name: Unspotted grunt
Order: Perciformes
Habitat: Brackish/Marine (Western Atlantic)
Scientific name: Pomadasys crocro
Name: Unus
Order: Perciformes
Habitat: Marine
Scientific name: Unus nigricans
Name: Upeneichthys
Order: Perciformes
Habitat: Temperate waters of Australia and New Zealand
Scientific name: Upeneichthys lineatus
Name: Upeneus
Order: Perciformes
Habitat: Indo-Pacific, coastal waters
Scientific name: Upeneus tragula
Name: Upeneus asymmetricus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus asymmetricus
Name: Upeneus australiae
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus australiae
Name: Upeneus davidaromi
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus davidaromi
Name: Upeneus francisi
Order: Perciformes
Habitat: Western Pacific
Scientific name: Upeneus francisi
Name: Upeneus gubal
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus gubal
Name: Upeneus ishiyamai
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus ishiyamai
Name: Upeneus lombok
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus lombok
Name: Upeneus luzonius
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus luzonius
Name: Upeneus margarethae
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus margarethae
Name: Upeneus mascarenie
Order: Perciformes
Habitat: Marine (Western Indian Ocean)
Scientific name: Upeneus mascarenie
Name: Upeneus moluccensis
Order: Perciformes
Habitat: Indo-Pacific, Red Sea, Mediterranean
Scientific name: Upeneus moluccensis
Name: Upeneus nigromarginatus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus nigromarginatus
Name: Upeneus oligospilus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus oligospilus
Name: Upeneus parvus
Order: Perciformes
Habitat: Western Atlantic
Scientific name: Upeneus parvus
Name: Upeneus pori
Order: Perciformes
Habitat: Eastern Mediterranean, Red Sea
Scientific name: Upeneus pori
Name: Upeneus quadrilineatus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus quadrilineatus
Name: Upeneus randalli
Order: Perciformes
Habitat: Marine (Eastern Atlantic)
Scientific name: Upeneus randalli
Name: Upeneus seychellensis
Order: Perciformes
Habitat: Western Indian Ocean
Scientific name: Upeneus seychellensis
Name: Upeneus stenopsis
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus stenopsis
Name: Upeneus sulphureus
Order: Perciformes
Habitat: Indo-Pacific
Scientific name: Upeneus sulphureus
Name: Upeneus sundaicus
Order: Perciformes
Habitat: Indo-Pacific
Scientific name: Upeneus sundaicus
Name: Upeneus taeniopterus
Order: Perciformes
Habitat: Indo-Pacific
Scientific name: Upeneus taeniopterus
Name: Upeneus tragula
Order: Perciformes
Habitat: Marine (Indo-Pacific)
Scientific name: Upeneus tragula
Name: Upeneus vanuatu
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus vanuatu
Name: Upeneus vittatus
Order: Perciformes
Habitat: Indo-Pacific, coastal and estuarine waters
Scientific name: Upeneus vittatus
Name: Upeneus xanthogrammus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Upeneus xanthogrammus
Name: Upland bully
Order: Gobiesociformes
Habitat: Freshwater (New Zealand)
Scientific name: Gobiomorphus breviceps
Name: Uracystia
Order: Cichliformes
Habitat: Freshwater
Scientific name: Uracystia flavolineata
Name: Uranocorynus
Order: Perciformes
Habitat: Marine
Scientific name: Uranocorynus holocentrus
Name: Uranoplosus
Order: Aulopiformes
Habitat: Marine
Scientific name: Uranoplosus filifer
Name: Uranops
Order: Perciformes
Habitat: Marine
Scientific name: Uranops microlepis
Name: Uranopsetta
Order: Pleuronectiformes
Habitat: Marine
Scientific name: Uranopsetta macrostoma
Name: Uranoscopus
Order: Perciformes
Habitat: Mediterranean Sea and adjacent Atlantic
Scientific name: Uranoscopus scaber
Name: Uranoscopus albesca
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus albesca
Name: Uranoscopus archionema
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus archionema
Name: Uranoscopus bicinctus
Order: Perciformes
Habitat: Indo-Pacific
Scientific name: Uranoscopus bicinctus
Name: Uranoscopus caudispinosus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus caudispinosus
Name: Uranoscopus chinensis
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus chinensis
Name: Uranoscopus cognatus
Order: Perciformes
Habitat: Western Pacific Ocean
Scientific name: Uranoscopus cognatus
Name: Uranoscopus crassiceps
Order: Perciformes
Habitat: Western Pacific Ocean
Scientific name: Uranoscopus crassiceps
Name: Uranoscopus dahlakensis
Order: Perciformes
Habitat: Marine (Red Sea)
Scientific name: Uranoscopus dahlakensis
Name: Uranoscopus dollfusi
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus dollfusi
Name: Uranoscopus elacups
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus elacups
Name: Uranoscopus filibarbus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus filibarbus
Name: Uranoscopus fuscomaculatus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus fuscomaculatus
Name: Uranoscopus guttatus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus guttatus
Name: Uranoscopus japonicus
Order: Perciformes
Habitat: Northwestern Pacific Ocean
Scientific name: Uranoscopus japonicus
Name: Uranoscopus javanicus
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus javanicus
Name: Uranoscopus kaianus
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus kaianus
Name: Uranoscopus leionema
Order: Perciformes
Habitat: Northwestern Pacific Ocean
Scientific name: Uranoscopus leionema
Name: Uranoscopus marisrubi
Order: Perciformes
Habitat: Marine (Red Sea)
Scientific name: Uranoscopus marisrubi
Name: Uranoscopus marisrubri
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus marisrubri
Name: Uranoscopus marmoratus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus marmoratus
Name: Uranoscopus nigripinnis
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus nigripinnis
Name: Uranoscopus oligolepis
Order: Perciformes
Habitat: Indo-Pacific
Scientific name: Uranoscopus oligolepis
Name: Uranoscopus orbicularis
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus orbicularis
Name: Uranoscopus orientalis
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus orientalis
Name: Uranoscopus persicus
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus persicus
Name: Uranoscopus polli
Order: Perciformes
Habitat: Marine (Eastern Atlantic)
Scientific name: Uranoscopus polli
Name: Uranoscopus scaber
Order: Perciformes
Habitat: Marine
Scientific name: Uranoscopus scaber
Name: Uranoscopus sulphureus
Order: Perciformes
Habitat: Marine (Indo-Pacific)
Scientific name: Uranoscopus sulphureus
Name: Uranoscopus terraereginae
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus terraereginae
Name: Uranoscopus tosae
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus tosae
Name: Uranoscopus xenogrammus
Order: Perciformes
Habitat: Marine (Western Pacific)
Scientific name: Uranoscopus xenogrammus
Name: Uranoscopus y-graecum
Order: Perciformes
Habitat: Western Atlantic Ocean
Scientific name: Uranoscopus y-graecum
Name: Uranoscopus yachi
Order: Perciformes
Habitat: Western Pacific Ocean
Scientific name: Uranoscopus yachi
Name: Uranoscopus yoshiae
Order: Perciformes
Habitat: Western Pacific Ocean
Scientific name: Uranoscopus yoshiae
Name: Uranotaenia
Order: Diptera
Habitat: Freshwater (Aquatic larvae)
Scientific name: Uranotaenia spp.
Name: Uranya
Order: Perciformes
Habitat: Marine
Scientific name: Uranya marmorata
Name: Urasoma
Order: Perciformes
Habitat: Marine
Scientific name: Urasoma nigripinnis
Name: Uraspis
Order: Perciformes
Habitat: Tropical and subtropical Indo-Pacific to Atlantic
Scientific name: Uraspis secunda
Name: Uraspis secunda
Order: Carangiformes
Habitat: Marine
Scientific name: Uraspis secunda
Name: Uraspis uraspis
Order: Carangiformes
Habitat: Marine
Scientific name: Uraspis uraspis
Name: Urataka
Order: Perciformes
Habitat: Marine
Scientific name: Urataka marginata
Name: Urchin Bass
Order: Perciformes
Habitat: Marine
Scientific name: Plectranthias nanus
Name: Ureche fish
Order: Siluriformes
Habitat: Freshwater (South America) – *Note: Local name refers to its ear-like structures.*
Scientific name: Anadoras weddellii
Name: Urechis
Order: Echiura
Habitat: Intertidal mudflats of East Asia
Scientific name: Urechis unicinctus
Name: Urechis caupo
Order: Annelida
Habitat: Marine
Scientific name: Urechis caupo
Name: Ureles
Order: Perciformes
Habitat: Indian Ocean
Scientific name: Ureles indicus
Name: Ureosoma
Order: Perciformes
Habitat: Marine
Scientific name: Ureosoma robustum
Name: Urephila
Order: Perciformes
Habitat: Marine
Scientific name: Urephila nigricans
Name: Uribia
Order: Characiformes
Habitat: Freshwater
Scientific name: Uribia venezuelensis
Name: Urochopus
Order: Perciformes
Habitat: Marine (Red Sea)
Scientific name: Urochopus erythraeus
Name: Uroconger
Order: Anguilliformes
Habitat: Marine
Scientific name: Uroconger lepturus
Name: Uroconger lepturus
Order: Anguilliformes
Habitat: Marine (Indo-Pacific)
Scientific name: Uroconger lepturus
Name: Uroconger syringinus
Order: Anguilliformes
Habitat: Marine (Western Atlantic)
Scientific name: Uroconger syringinus
Name: Uroconger vittatus
Order: Anguilliformes
Habitat: Marine (Central Pacific)
Scientific name: Uroconger vittatus
Name: Urocoptes
Order: Anguilliformes
Habitat: Marine
Scientific name: Urocoptes squamatus
Name: Urocryptus
Order: Anguilliformes
Habitat: Marine
Scientific name: Urocryptus micropterus
Name: Urogymnus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urogymnus asperrimus
Name: Urolepis
Order: Perciformes
Habitat: Marine
Scientific name: Urolepis pectoralis
Name: Urolepis regularis
Order: Pleuronectiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urolepis regularis
Name: Uroleptus
Order: Perciformes
Habitat: Marine
Scientific name: Uroleptus longirostris
Name: Urolophoides
Order: Urolophiformes
Habitat: Marine
Scientific name: Urolophoides armatus
Name: Urolophoides kaianus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophoides kaianus
Name: Urolophus
Order: Myliobatiformes
Habitat: Coastal waters of Australia
Scientific name: Urolophus testaceus
Name: Urolophus armatus
Order: Myliobatiformes
Habitat: Western Pacific
Scientific name: Urolophus armatus
Name: Urolophus aurantiacus
Order: Myliobatiformes
Habitat: Marine (Western Pacific)
Scientific name: Urolophus aurantiacus
Name: Urolophus bucculentus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus bucculentus
Name: Urolophus chlorophthalmus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus chlorophthalmus
Name: Urolophus concentricus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus concentricus
Name: Urolophus cruciatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus cruciatus
Name: Urolophus expansus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus expansus
Name: Urolophus gigas
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus gigas
Name: Urolophus guttatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus guttatus
Name: Urolophus javanicus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus javanicus
Name: Urolophus kabaenensis
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus kabaenensis
Name: Urolophus kaianus
Order: Myliobatiformes
Habitat: Western Pacific Ocean
Scientific name: Urolophus kaianus
Name: Urolophus lobatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus lobatus
Name: Urolophus maculatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus maculatus
Name: Urolophus mendosoma
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus mendosoma
Name: Urolophus mitosis
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus mitosis
Name: Urolophus mucosus
Order: Myliobatiformes
Habitat: Marine (Western Australia)
Scientific name: Urolophus mucosus
Name: Urolophus neocaledoniensis
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus neocaledoniensis
Name: Urolophus nigricaudatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus nigricaudatus
Name: Urolophus nigricaudus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus nigricaudus
Name: Urolophus ogilbyi
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus ogilbyi
Name: Urolophus orarius
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus orarius
Name: Urolophus papilio
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus papilio
Name: Urolophus parvipinnis
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus parvipinnis
Name: Urolophus paucimaculatus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus paucimaculatus
Name: Urolophus piperitus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus piperitus
Name: Urolophus pseudomedia
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus pseudomedia
Name: Urolophus skeletomus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus skeletomus
Name: Urolophus sufflavus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus sufflavus
Name: Urolophus tenuirictus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus tenuirictus
Name: Urolophus testaceus
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus testaceus
Name: Urolophus viridis
Order: Myliobatiformes
Habitat: Marine (Eastern Australia)
Scientific name: Urolophus viridis
Name: Urolophus wellingtoni
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus wellingtoni
Name: Urolophus westraliensis
Order: Myliobatiformes
Habitat: Marine
Scientific name: Urolophus westraliensis
Name: Urophycis
Order: Gadiformes
Habitat: Marine
Scientific name: Urophycis chuss
Name: Urophycis chesteri
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis chesteri
Name: Urophycis chuss
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis chuss
Name: Urophycis cirrata
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis cirrata
Name: Urophycis earllii
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis earllii
Name: Urophycis florida
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis florida
Name: Urophycis mystacea
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis mystacea
Name: Urophycis regia
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis regia
Name: Urophycis tenuis
Order: Gadiformes
Habitat: Marine (Western Atlantic)
Scientific name: Urophycis tenuis
Name: Uropterygioides
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygioides xenodon
Name: Uropterygius
Order: Anguilliformes
Habitat: Indo-Pacific, rocky and coral reefs
Scientific name: Uropterygius macrocephalus
Name: Uropterygius concolor
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius concolor
Name: Uropterygius fasciolatus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius fasciolatus
Name: Uropterygius fijiensis
Order: Anguilliformes
Habitat: Marine (Central Pacific)
Scientific name: Uropterygius fijiensis
Name: Uropterygius fuscoguttatus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius fuscoguttatus
Name: Uropterygius genie
Order: Anguilliformes
Habitat: Marine (Western Pacific)
Scientific name: Uropterygius genie
Name: Uropterygius golanii
Order: Anguilliformes
Habitat: Marine (Red Sea)
Scientific name: Uropterygius golanii
Name: Uropterygius inornatus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius inornatus
Name: Uropterygius kamar
Order: Anguilliformes
Habitat: Marine (Western Pacific)
Scientific name: Uropterygius kamar
Name: Uropterygius macrocephalus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius macrocephalus
Name: Uropterygius macularius
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius macularius
Name: Uropterygius makatei
Order: Anguilliformes
Habitat: Marine (Central Pacific)
Scientific name: Uropterygius makatei
Name: Uropterygius marmoratus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius marmoratus
Name: Uropterygius micropterus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius micropterus
Name: Uropterygius nagoensis
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius nagoensis
Name: Uropterygius necturus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius necturus
Name: Uropterygius oligospondylus
Order: Anguilliformes
Habitat: Marine (Western Pacific)
Scientific name: Uropterygius oligospondylus
Name: Uropterygius palmeri
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius palmeri
Name: Uropterygius platyrhynchus
Order: Anguilliformes
Habitat: Marine (Indo-Pacific)
Scientific name: Uropterygius platyrhynchus
Name: Uropterygius polyspilus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius polyspilus
Name: Uropterygius praepes
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius praepes
Name: Uropterygius sealei
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius sealei
Name: Uropterygius selachops
Order: Anguilliformes
Habitat: Marine (Western Pacific)
Scientific name: Uropterygius selachops
Name: Uropterygius sewelli
Order: Anguilliformes
Habitat: Marine (Western Indian Ocean)
Scientific name: Uropterygius sewelli
Name: Uropterygius supraforatus
Order: Anguilliformes
Habitat: Marine (Indo-Pacific)
Scientific name: Uropterygius supraforatus
Name: Uropterygius tigrinus
Order: Anguilliformes
Habitat: Marine
Scientific name: Uropterygius tigrinus
Name: Uropterygius xenodontus
Order: Anguilliformes
Habitat: Marine (Western Pacific)
Scientific name: Uropterygius xenodontus
Name: Ursa Major
Order: Carangiformes
Habitat: Marine (Atlantic Ocean) – *Note: Common name sometimes used for Horse-eye Jack due to size.*
Scientific name: Caranx hippos
Name: Ursinus
Order: Perciformes
Habitat: Freshwater
Scientific name: Ursinus microlepis
Name: Ursula
Order: Perciformes
Habitat: Marine
Scientific name: Ursula macrocephala
Name: Uruguayan Leopard Catfish
Order: Siluriformes
Habitat: Freshwater
Scientific name: Loricariichthys anus
Name: Usacaranx
Order: Carangiformes
Habitat: Marine (Western Pacific)
Scientific name: Usacaranx noorderlandensis
Name: Ustjuzhanin's loach
Order: Cypriniformes
Habitat: Freshwater (Central Asia)
Scientific name: Oxynoemacheilus ustjuzhanini
Name: Usuarius
Order: Perciformes
Habitat: Marine
Scientific name: Usuarius microlepis
Name: Utah Chub
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Gila atraria
Name: Utah chub
Order: Cypriniformes
Habitat: Freshwater (North America)
Scientific name: Gila atraria
Name: Utah sucker
Order: Cypriniformes
Habitat: Freshwater (North America) – *Note: Extinct.*
Scientific name: Chasmistes muriei
Name: Utaka
Order: Cichliformes
Habitat: Freshwater
Scientific name: Utaka fusiformis
Name: Utaka cichlid
Order: Cichliformes
Habitat: Freshwater (Lake Malawi)
Scientific name: Copadichromis borleyi
Name: Ute cichlid
Order: Cichliformes
Habitat: Freshwater (Lake Malawi)
Scientific name: Chindongo saulosi
Name: Utes
Order: Perciformes
Habitat: Marine
Scientific name: Utes longispinus
Name: Utopia
Order: Cypriniformes
Habitat: Freshwater
Scientific name: Utopia notoptera
Name: Utricularius
Order: Lophiiformes
Habitat: Marine
Scientific name: Utricularius maculatus
Name: Uwakita
Order: Perciformes
Habitat: Marine
Scientific name: Uwakita japonica
| Name | Order | Habitat | Scientific name |
|---|---|---|---|
| Uaru | Cichliformes | Freshwater | Uaru amphiacanthoides |
| Uaru cichlid | Cichliformes | Freshwater (Amazon Basin) | Uaru amphiacanthoides |
| Uaru-tucuxi | Cichliformes | Freshwater | Symphysodon sp. 'tucuxi' |
| Ubiquitous Gourami | Anabantiformes | Southeast Asia | Trichopsis vittata |
| Uca | Gobiiformes | Brackish | Uca pugnax |
| Uca annulipes | Decapoda | Brackish (Indo-Pacific estuaries) | Uca annulipes |
| Uca argus | Decapoda | Brackish (East Atlantic estuaries) | Uca argus |
| Uca borealis | Decapoda | Marine/Brackish | Uca borealis |
| Uca coarctata | Decapoda | Brackish (Indo-Pacific estuaries) | Uca coarctata |
| Uca crassipes | Decapoda | Brackish (Indo-Pacific estuaries) | Uca crassipes |
| Uca dussumieri | Decapoda | Brackish (Indo-Pacific estuaries) | Uca dussumieri |
| Uca elegans | Decapoda | Brackish (East Pacific estuaries) | Uca elegans |
| Uca flammula | Decapoda | Brackish (Indo-Pacific estuaries) | Uca flammula |
| Uca forcipata | Decapoda | Marine/Brackish | Uca forcipata |
| Uca lactea | Decapoda | Brackish (Indo-Pacific estuaries) | Uca lactea |
| Uca longirostris | Decapoda | Brackish (East Pacific estuaries) | Uca longirostris |
| Uca princeps | Decapoda | Marine/Brackish | Uca princeps |
| Uca pugilator | Decapoda | Marine/Brackish | Uca pugilator |
| Uca pugnax | Decapoda | Brackish (Western Atlantic estuaries) | Uca pugnax |
| Uca rapax | Decapoda | Marine/Brackish | Uca rapax |
| Uca speciosa | Decapoda | Marine/Brackish | Uca speciosa |
| Uca tangeri | Decapoda | Marine/Brackish | Uca tangeri |
| Uca triangularis | Decapoda | Brackish (Indo-Pacific estuaries) | Uca triangularis |
| Udara | Perciformes | Marine | Udara dussumieri |
| Uechi | Perciformes | Marine | Uechi notatus |
| Ugandian Lungfish | Ceratodontiformes | Freshwater | Protopterus aethiopicus |
| Ugobrasse | Perciformes | Marine (South Atlantic) | Acanthistius brasilianus |
| Uhde's Parrotfish | Perciformes | Marine | Scarus coeruleus |
| Ula | Perciformes | Marine | Ula hypseloptera |
| Ulah | Siluriformes | Freshwater | Ulah microphthalmus |
| Ulcerfish | Perciformes | Marine | Ulcerfish anomala |
| Ulua | Carangiformes | Marine | Ulua mentalis |
| Ulupora | Perciformes | Marine | Ulupora bimaculata |
| Ulupora brachycentra | Perciformes | Marine (Western Pacific) | Ulupora brachycentra |
| Ulupora macrolepis | Perciformes | Marine (Western Pacific) | Ulupora macrolepis |
| Uluulu | Perciformes | Marine | Uluulu akule |
| Ulva Sea Bream | Spariformes | Marine | Boops boops |
| Ulzana | Perciformes | Freshwater/Brackish | Ambassis urotaenia |
| Uma | Tetraodontiformes | Marine | Uma umbra |
| Umaki | Tetraodontiformes | Marine | Umaki bicolor |
| Umbeli | Perciformes | Marine | Umbeli unicolor |
| Umbellow | Perciformes | Marine | Dasyatis pastinaca |
| Umbili | Perciformes | Marine | Umbili punctata |
| Umbra | Esociformes | Freshwaters of Europe | Umbra krameri |
| Umbraculum | Perciformes | Marine | Umbraculum sinense |
| Umbramina | Perciformes | Marine | Umbramina striata |
| Umbramora | Gadiformes | Marine | Umbramora jacksoni |
| Umbrella Anthias | Perciformes | Marine | Anthias squamipinnis |
| Umbrella Guppy | Cyprinodontiformes | Freshwater | Poecilia reticulata (Umbrella variety) |
| Umbrella Mouth Catfish | Siluriformes | Freshwater | Phreatobius cisternarum |
| Umbrella Squid | Teuthida | Marine | Graneledone boreopacifica |
| Umbrella characin | Characiformes | Freshwater (South America) | Triportheus angulatus |
| Umbrellafish | Batrachoidiformes | Marine (Western Atlantic) | Opsanus beta |
| Umbrina | Perciformes | Coastal waters of the Atlantic and Mediterranean | Umbrina cirrosa |
| Umbrina analis | Perciformes | Eastern Atlantic | Umbrina analis |
| Umbrina broussonnetii | Perciformes | Eastern Atlantic | Umbrina broussonnetii |
| Umbrina canariensis | Perciformes | Eastern Atlantic, Mediterranean | Umbrina canariensis |
| Umbrina coroides | Perciformes | Western Atlantic | Umbrina coroides |
| Umbrina galapagorum | Perciformes | Eastern Pacific, Galapagos Islands | Umbrina galapagorum |
| Umbrina imberbis | Perciformes | Marine (East Pacific) | Umbrina imberbis |
| Umbrina milliae | Perciformes | Marine | Umbrina milliae |
| Umbrina musae | Perciformes | Marine | Umbrina musae |
| Umbrina reedi | Perciformes | Marine (East Pacific) | Umbrina reedi |
| Umbrina richardi | Perciformes | Marine | Umbrina richardi |
| Umbrina robusta | Perciformes | Eastern Atlantic | Umbrina robusta |
| Umbrina roncador | Perciformes | Eastern Pacific | Umbrina roncador |
| Umbrina ronchus | Perciformes | Marine | Umbrina ronchus |
| Umbrina steindachneri | Perciformes | Eastern Pacific | Umbrina steindachneri |
| Umbrina xanti | Perciformes | Marine (East Pacific) | Umbrina xanti |
| Umeboshi | Tetraodontiformes | Marine | Umeboshi lunulata |
| Unakagin | Anguilliformes | Marine | Unakagin nigromarginata |
| Unati | Characiformes | Freshwater | Unati pinnata |
| Unbanded Goatfish | Perciformes | Marine | Upeneus sulphureus |
| Uncia | Siluriformes | Freshwater | Uncia fasciolata |
| Undertakerfish | Lophiiformes | Marine | Undertakerfish lugubris |
| Unicorn Anchovy | Clupeiformes | Marine | Setipinna taty |
| Unicorn Blenny | Blenniiformes | Marine | Meiacanthus kamoharai |
| Unicorn Fish | Acanthuriformes | Tropical and subtropical Indo-Pacific | Naso unicornis |
| Unicorn Leatherjacket | Tetraodontiformes | Marine | Aluterus monoceros |
| Unicorn Surgeonfish | Perciformes | Marine | Naso unicornis |
| Unicorn Triggerfish | Tetraodontiformes | Marine | Balistapus undulatus |
| Unicorn Wrasse | Labriformes | Marine | Hemigymnus fasciatus |
| Unicorn filefish | Tetraodontiformes | Marine (Tropical/Subtropical worldwide) | Aluterus monoceros |
| Unicorn leatherjacket | Tetraodontiformes | Marine (Tropical/Subtropical worldwide) | Aluterus monoceros |
| Unicorn tang | Acanthuriformes | Marine (Indo-Pacific) | Naso unicornis |
| Unicornfish | Myctophiformes | Marine (Deep sea) | Macrostoma mirabilis |
| Unidentified Anglerfish (U-species) | Lophiiformes | Marine (Deep-sea) | Various unknown species |
| Unidentified Cichlid (U-species) | Cichliformes | Freshwater | Various unknown species |
| Unidentified Eel (U-species) | Anguilliformes | Marine | Various unknown species |
| Unidentified Goby (U-species) | Gobiiformes | Marine/Freshwater | Various unknown species |
| Unidentified Hake (U-species) | Gadiformes | Marine | Various unknown species |
| Unidentified Moray Eel (U-species) | Anguilliformes | Marine | Gymnothorax undulatus |
| Unidentified Rockfish (U-species) | Scorpaeniformes | Marine | Various unknown species |
| Unidentified Shark (U-species) | Selachimorpha | Marine | Various unknown species |
| Unidentified Skark (U-species) | Rajiformes | Marine | Various unknown species |
| Unidentified Snapper (U-species) | Perciformes | Marine | Lutjanus sp. |
| Unilocular | Perciformes | Marine | Unilocular maculatus |
| Unio | Cypriniformes | Freshwater | Unio pictorum |
| Uniped fish | Siluriformes | Freshwater (Somalia; cave dweller) – *Note: Often used in context of having only one pair of fins.* | Phreatichthys andersoni |
| Unipedal fish | Tetraodontiformes | Freshwater of Southeast Asia (a common name for some puffers) | Tetraodon fluviatilis |
| Unique cichlid | Cichliformes | Freshwater (Lake Tanganyika) | Lamprologus ornatipinnis |
| Uniramia | Perciformes | Marine | Uniramia viridis |
| Unka | Cypriniformes | Freshwater | Unka barbata |
| Unkaria | Cypriniformes | Freshwater | Unkaria robusta |
| Unknown cichlid | Cichliformes | Freshwater (Lake Tanganyika) | Trematocara macrostoma |
| Unkus | Cypriniformes | Freshwater | Unkus fuscus |
| Unpaved Scad | Carangiformes | Marine | Decapterus macarellus |
| Unspotted Catshark | Carcharhiniformes | Marine | Atelomycterus macleayi |
| Unspotted Flounder | Pleuronectiformes | Marine | Pseudorhombus arsius |
| Unspotted Grunt | Perciformes | Marine | Pomadasys commersonnii |
| Unspotted Puffer | Tetraodontiformes | Marine | Arothron nigropunctatus |
| Unspotted Stingray | Myliobatiformes | Marine | Neotrygon kuhlii |
| Unspotted Triggerfish | Tetraodontiformes | Marine | Balistes capriscus |
| Unspotted grunt | Perciformes | Brackish/Marine (Western Atlantic) | Pomadasys crocro |
| Unus | Perciformes | Marine | Unus nigricans |
| Upeneichthys | Perciformes | Temperate waters of Australia and New Zealand | Upeneichthys lineatus |
| Upeneus | Perciformes | Indo-Pacific, coastal waters | Upeneus tragula |
| Upeneus asymmetricus | Perciformes | Marine (Western Pacific) | Upeneus asymmetricus |
| Upeneus australiae | Perciformes | Marine (Western Pacific) | Upeneus australiae |
| Upeneus davidaromi | Perciformes | Marine (Western Pacific) | Upeneus davidaromi |
| Upeneus francisi | Perciformes | Western Pacific | Upeneus francisi |
| Upeneus gubal | Perciformes | Marine (Western Pacific) | Upeneus gubal |
| Upeneus ishiyamai | Perciformes | Marine (Western Pacific) | Upeneus ishiyamai |
| Upeneus lombok | Perciformes | Marine (Western Pacific) | Upeneus lombok |
| Upeneus luzonius | Perciformes | Marine (Western Pacific) | Upeneus luzonius |
| Upeneus margarethae | Perciformes | Marine (Western Pacific) | Upeneus margarethae |
| Upeneus mascarenie | Perciformes | Marine (Western Indian Ocean) | Upeneus mascarenie |
| Upeneus moluccensis | Perciformes | Indo-Pacific, Red Sea, Mediterranean | Upeneus moluccensis |
| Upeneus nigromarginatus | Perciformes | Marine (Western Pacific) | Upeneus nigromarginatus |
| Upeneus oligospilus | Perciformes | Marine (Western Pacific) | Upeneus oligospilus |
| Upeneus parvus | Perciformes | Western Atlantic | Upeneus parvus |
| Upeneus pori | Perciformes | Eastern Mediterranean, Red Sea | Upeneus pori |
| Upeneus quadrilineatus | Perciformes | Marine (Western Pacific) | Upeneus quadrilineatus |
| Upeneus randalli | Perciformes | Marine (Eastern Atlantic) | Upeneus randalli |
| Upeneus seychellensis | Perciformes | Western Indian Ocean | Upeneus seychellensis |
| Upeneus stenopsis | Perciformes | Marine (Western Pacific) | Upeneus stenopsis |
| Upeneus sulphureus | Perciformes | Indo-Pacific | Upeneus sulphureus |
| Upeneus sundaicus | Perciformes | Indo-Pacific | Upeneus sundaicus |
| Upeneus taeniopterus | Perciformes | Indo-Pacific | Upeneus taeniopterus |
| Upeneus tragula | Perciformes | Marine (Indo-Pacific) | Upeneus tragula |
| Upeneus vanuatu | Perciformes | Marine (Western Pacific) | Upeneus vanuatu |
| Upeneus vittatus | Perciformes | Indo-Pacific, coastal and estuarine waters | Upeneus vittatus |
| Upeneus xanthogrammus | Perciformes | Marine (Western Pacific) | Upeneus xanthogrammus |
| Upland bully | Gobiesociformes | Freshwater (New Zealand) | Gobiomorphus breviceps |
| Uracystia | Cichliformes | Freshwater | Uracystia flavolineata |
| Uranocorynus | Perciformes | Marine | Uranocorynus holocentrus |
| Uranoplosus | Aulopiformes | Marine | Uranoplosus filifer |
| Uranops | Perciformes | Marine | Uranops microlepis |
| Uranopsetta | Pleuronectiformes | Marine | Uranopsetta macrostoma |
| Uranoscopus | Perciformes | Mediterranean Sea and adjacent Atlantic | Uranoscopus scaber |
| Uranoscopus albesca | Perciformes | Marine | Uranoscopus albesca |
| Uranoscopus archionema | Perciformes | Marine (Western Pacific) | Uranoscopus archionema |
| Uranoscopus bicinctus | Perciformes | Indo-Pacific | Uranoscopus bicinctus |
| Uranoscopus caudispinosus | Perciformes | Marine (Western Pacific) | Uranoscopus caudispinosus |
| Uranoscopus chinensis | Perciformes | Marine (Western Pacific) | Uranoscopus chinensis |
| Uranoscopus cognatus | Perciformes | Western Pacific Ocean | Uranoscopus cognatus |
| Uranoscopus crassiceps | Perciformes | Western Pacific Ocean | Uranoscopus crassiceps |
| Uranoscopus dahlakensis | Perciformes | Marine (Red Sea) | Uranoscopus dahlakensis |
| Uranoscopus dollfusi | Perciformes | Marine | Uranoscopus dollfusi |
| Uranoscopus elacups | Perciformes | Marine (Western Pacific) | Uranoscopus elacups |
| Uranoscopus filibarbus | Perciformes | Marine (Western Pacific) | Uranoscopus filibarbus |
| Uranoscopus fuscomaculatus | Perciformes | Marine (Western Pacific) | Uranoscopus fuscomaculatus |
| Uranoscopus guttatus | Perciformes | Marine (Western Pacific) | Uranoscopus guttatus |
| Uranoscopus japonicus | Perciformes | Northwestern Pacific Ocean | Uranoscopus japonicus |
| Uranoscopus javanicus | Perciformes | Marine | Uranoscopus javanicus |
| Uranoscopus kaianus | Perciformes | Marine | Uranoscopus kaianus |
| Uranoscopus leionema | Perciformes | Northwestern Pacific Ocean | Uranoscopus leionema |
| Uranoscopus marisrubi | Perciformes | Marine (Red Sea) | Uranoscopus marisrubi |
| Uranoscopus marisrubri | Perciformes | Marine | Uranoscopus marisrubri |
| Uranoscopus marmoratus | Perciformes | Marine (Western Pacific) | Uranoscopus marmoratus |
| Uranoscopus nigripinnis | Perciformes | Marine (Western Pacific) | Uranoscopus nigripinnis |
| Uranoscopus oligolepis | Perciformes | Indo-Pacific | Uranoscopus oligolepis |
| Uranoscopus orbicularis | Perciformes | Marine | Uranoscopus orbicularis |
| Uranoscopus orientalis | Perciformes | Marine (Western Pacific) | Uranoscopus orientalis |
| Uranoscopus persicus | Perciformes | Marine | Uranoscopus persicus |
| Uranoscopus polli | Perciformes | Marine (Eastern Atlantic) | Uranoscopus polli |
| Uranoscopus scaber | Perciformes | Marine | Uranoscopus scaber |
| Uranoscopus sulphureus | Perciformes | Marine (Indo-Pacific) | Uranoscopus sulphureus |
| Uranoscopus terraereginae | Perciformes | Marine (Western Pacific) | Uranoscopus terraereginae |
| Uranoscopus tosae | Perciformes | Marine (Western Pacific) | Uranoscopus tosae |
| Uranoscopus xenogrammus | Perciformes | Marine (Western Pacific) | Uranoscopus xenogrammus |
| Uranoscopus y-graecum | Perciformes | Western Atlantic Ocean | Uranoscopus y-graecum |
| Uranoscopus yachi | Perciformes | Western Pacific Ocean | Uranoscopus yachi |
| Uranoscopus yoshiae | Perciformes | Western Pacific Ocean | Uranoscopus yoshiae |
| Uranotaenia | Diptera | Freshwater (Aquatic larvae) | Uranotaenia spp. |
| Uranya | Perciformes | Marine | Uranya marmorata |
| Urasoma | Perciformes | Marine | Urasoma nigripinnis |
| Uraspis | Perciformes | Tropical and subtropical Indo-Pacific to Atlantic | Uraspis secunda |
| Uraspis secunda | Carangiformes | Marine | Uraspis secunda |
| Uraspis uraspis | Carangiformes | Marine | Uraspis uraspis |
| Urataka | Perciformes | Marine | Urataka marginata |
| Urchin Bass | Perciformes | Marine | Plectranthias nanus |
| Ureche fish | Siluriformes | Freshwater (South America) – *Note: Local name refers to its ear-like structures.* | Anadoras weddellii |
| Urechis | Echiura | Intertidal mudflats of East Asia | Urechis unicinctus |
| Urechis caupo | Annelida | Marine | Urechis caupo |
| Ureles | Perciformes | Indian Ocean | Ureles indicus |
| Ureosoma | Perciformes | Marine | Ureosoma robustum |
| Urephila | Perciformes | Marine | Urephila nigricans |
| Uribia | Characiformes | Freshwater | Uribia venezuelensis |
| Urochopus | Perciformes | Marine (Red Sea) | Urochopus erythraeus |
| Uroconger | Anguilliformes | Marine | Uroconger lepturus |
| Uroconger lepturus | Anguilliformes | Marine (Indo-Pacific) | Uroconger lepturus |
| Uroconger syringinus | Anguilliformes | Marine (Western Atlantic) | Uroconger syringinus |
| Uroconger vittatus | Anguilliformes | Marine (Central Pacific) | Uroconger vittatus |
| Urocoptes | Anguilliformes | Marine | Urocoptes squamatus |
| Urocryptus | Anguilliformes | Marine | Urocryptus micropterus |
| Urogymnus | Myliobatiformes | Marine | Urogymnus asperrimus |
| Urolepis | Perciformes | Marine | Urolepis pectoralis |
| Urolepis regularis | Pleuronectiformes | Marine (Western Atlantic) | Urolepis regularis |
| Uroleptus | Perciformes | Marine | Uroleptus longirostris |
| Urolophoides | Urolophiformes | Marine | Urolophoides armatus |
| Urolophoides kaianus | Myliobatiformes | Marine | Urolophoides kaianus |
| Urolophus | Myliobatiformes | Coastal waters of Australia | Urolophus testaceus |
| Urolophus armatus | Myliobatiformes | Western Pacific | Urolophus armatus |
| Urolophus aurantiacus | Myliobatiformes | Marine (Western Pacific) | Urolophus aurantiacus |
| Urolophus bucculentus | Myliobatiformes | Marine | Urolophus bucculentus |
| Urolophus chlorophthalmus | Myliobatiformes | Marine | Urolophus chlorophthalmus |
| Urolophus concentricus | Myliobatiformes | Marine | Urolophus concentricus |
| Urolophus cruciatus | Myliobatiformes | Marine | Urolophus cruciatus |
| Urolophus expansus | Myliobatiformes | Marine | Urolophus expansus |
| Urolophus gigas | Myliobatiformes | Marine | Urolophus gigas |
| Urolophus guttatus | Myliobatiformes | Marine | Urolophus guttatus |
| Urolophus javanicus | Myliobatiformes | Marine | Urolophus javanicus |
| Urolophus kabaenensis | Myliobatiformes | Marine | Urolophus kabaenensis |
| Urolophus kaianus | Myliobatiformes | Western Pacific Ocean | Urolophus kaianus |
| Urolophus lobatus | Myliobatiformes | Marine | Urolophus lobatus |
| Urolophus maculatus | Myliobatiformes | Marine | Urolophus maculatus |
| Urolophus mendosoma | Myliobatiformes | Marine | Urolophus mendosoma |
| Urolophus mitosis | Myliobatiformes | Marine | Urolophus mitosis |
| Urolophus mucosus | Myliobatiformes | Marine (Western Australia) | Urolophus mucosus |
| Urolophus neocaledoniensis | Myliobatiformes | Marine | Urolophus neocaledoniensis |
| Urolophus nigricaudatus | Myliobatiformes | Marine | Urolophus nigricaudatus |
| Urolophus nigricaudus | Myliobatiformes | Marine | Urolophus nigricaudus |
| Urolophus ogilbyi | Myliobatiformes | Marine | Urolophus ogilbyi |
| Urolophus orarius | Myliobatiformes | Marine | Urolophus orarius |
| Urolophus papilio | Myliobatiformes | Marine | Urolophus papilio |
| Urolophus parvipinnis | Myliobatiformes | Marine | Urolophus parvipinnis |
| Urolophus paucimaculatus | Myliobatiformes | Marine | Urolophus paucimaculatus |
| Urolophus piperitus | Myliobatiformes | Marine | Urolophus piperitus |
| Urolophus pseudomedia | Myliobatiformes | Marine | Urolophus pseudomedia |
| Urolophus skeletomus | Myliobatiformes | Marine | Urolophus skeletomus |
| Urolophus sufflavus | Myliobatiformes | Marine | Urolophus sufflavus |
| Urolophus tenuirictus | Myliobatiformes | Marine | Urolophus tenuirictus |
| Urolophus testaceus | Myliobatiformes | Marine | Urolophus testaceus |
| Urolophus viridis | Myliobatiformes | Marine (Eastern Australia) | Urolophus viridis |
| Urolophus wellingtoni | Myliobatiformes | Marine | Urolophus wellingtoni |
| Urolophus westraliensis | Myliobatiformes | Marine | Urolophus westraliensis |
| Urophycis | Gadiformes | Marine | Urophycis chuss |
| Urophycis chesteri | Gadiformes | Marine (Western Atlantic) | Urophycis chesteri |
| Urophycis chuss | Gadiformes | Marine (Western Atlantic) | Urophycis chuss |
| Urophycis cirrata | Gadiformes | Marine (Western Atlantic) | Urophycis cirrata |
| Urophycis earllii | Gadiformes | Marine (Western Atlantic) | Urophycis earllii |
| Urophycis florida | Gadiformes | Marine (Western Atlantic) | Urophycis florida |
| Urophycis mystacea | Gadiformes | Marine (Western Atlantic) | Urophycis mystacea |
| Urophycis regia | Gadiformes | Marine (Western Atlantic) | Urophycis regia |
| Urophycis tenuis | Gadiformes | Marine (Western Atlantic) | Urophycis tenuis |
| Uropterygioides | Anguilliformes | Marine | Uropterygioides xenodon |
| Uropterygius | Anguilliformes | Indo-Pacific, rocky and coral reefs | Uropterygius macrocephalus |
| Uropterygius concolor | Anguilliformes | Marine | Uropterygius concolor |
| Uropterygius fasciolatus | Anguilliformes | Marine | Uropterygius fasciolatus |
| Uropterygius fijiensis | Anguilliformes | Marine (Central Pacific) | Uropterygius fijiensis |
| Uropterygius fuscoguttatus | Anguilliformes | Marine | Uropterygius fuscoguttatus |
| Uropterygius genie | Anguilliformes | Marine (Western Pacific) | Uropterygius genie |
| Uropterygius golanii | Anguilliformes | Marine (Red Sea) | Uropterygius golanii |
| Uropterygius inornatus | Anguilliformes | Marine | Uropterygius inornatus |
| Uropterygius kamar | Anguilliformes | Marine (Western Pacific) | Uropterygius kamar |
| Uropterygius macrocephalus | Anguilliformes | Marine | Uropterygius macrocephalus |
| Uropterygius macularius | Anguilliformes | Marine | Uropterygius macularius |
| Uropterygius makatei | Anguilliformes | Marine (Central Pacific) | Uropterygius makatei |
| Uropterygius marmoratus | Anguilliformes | Marine | Uropterygius marmoratus |
| Uropterygius micropterus | Anguilliformes | Marine | Uropterygius micropterus |
| Uropterygius nagoensis | Anguilliformes | Marine | Uropterygius nagoensis |
| Uropterygius necturus | Anguilliformes | Marine | Uropterygius necturus |
| Uropterygius oligospondylus | Anguilliformes | Marine (Western Pacific) | Uropterygius oligospondylus |
| Uropterygius palmeri | Anguilliformes | Marine | Uropterygius palmeri |
| Uropterygius platyrhynchus | Anguilliformes | Marine (Indo-Pacific) | Uropterygius platyrhynchus |
| Uropterygius polyspilus | Anguilliformes | Marine | Uropterygius polyspilus |
| Uropterygius praepes | Anguilliformes | Marine | Uropterygius praepes |
| Uropterygius sealei | Anguilliformes | Marine | Uropterygius sealei |
| Uropterygius selachops | Anguilliformes | Marine (Western Pacific) | Uropterygius selachops |
| Uropterygius sewelli | Anguilliformes | Marine (Western Indian Ocean) | Uropterygius sewelli |
| Uropterygius supraforatus | Anguilliformes | Marine (Indo-Pacific) | Uropterygius supraforatus |
| Uropterygius tigrinus | Anguilliformes | Marine | Uropterygius tigrinus |
| Uropterygius xenodontus | Anguilliformes | Marine (Western Pacific) | Uropterygius xenodontus |
| Ursa Major | Carangiformes | Marine (Atlantic Ocean) – *Note: Common name sometimes used for Horse-eye Jack due to size.* | Caranx hippos |
| Ursinus | Perciformes | Freshwater | Ursinus microlepis |
| Ursula | Perciformes | Marine | Ursula macrocephala |
| Uruguayan Leopard Catfish | Siluriformes | Freshwater | Loricariichthys anus |
| Usacaranx | Carangiformes | Marine (Western Pacific) | Usacaranx noorderlandensis |
| Ustjuzhanin's loach | Cypriniformes | Freshwater (Central Asia) | Oxynoemacheilus ustjuzhanini |
| Usuarius | Perciformes | Marine | Usuarius microlepis |
| Utah Chub | Cypriniformes | Freshwater | Gila atraria |
| Utah chub | Cypriniformes | Freshwater (North America) | Gila atraria |
| Utah sucker | Cypriniformes | Freshwater (North America) – *Note: Extinct.* | Chasmistes muriei |
| Utaka | Cichliformes | Freshwater | Utaka fusiformis |
| Utaka cichlid | Cichliformes | Freshwater (Lake Malawi) | Copadichromis borleyi |
| Ute cichlid | Cichliformes | Freshwater (Lake Malawi) | Chindongo saulosi |
| Utes | Perciformes | Marine | Utes longispinus |
| Utopia | Cypriniformes | Freshwater | Utopia notoptera |
| Utricularius | Lophiiformes | Marine | Utricularius maculatus |
| Uwakita | Perciformes | Marine | Uwakita japonica |