Mullidae
Elongate goatfish
Upeneus elongatus
FISH SPECIES
Flat-bodied Fish
Compare fish with laterally compressed, dorsoventrally depressed or asymmetrical body plans across habitats.
FISH ATLAS / FIELD GUIDEFlat FishIN THIS CHAPTER01 / Characteristics02 / Lifestyle03 / Species04 / Field notes
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01 / NATURAL HISTORY
Characteristics
Flattened body forms represent two distinct evolutionary paths: laterally compressed forms engineered for agility in narrow vertical spaces, and dorsoventrally depressed or asymmetrical forms specialized for living flush against the ocean floor.
- 01Laterally compressed maneuvering
- 02Dorsoventrally flattened resting
- 03Benthic sediment concealment
02 / LIFESTYLE
Lifestyle
Laterally compressed fishes like butterflyfishes and batfishes orient vertically to dart through intricate reef branches, using broad median fins to execute instantaneous, low-radius pivot turns. In stark contrast, depressed rays and asymmetrical flatfishes bury beneath sediment with only elevated eyes exposed, remaining completely motionless until striking passing prey from underneath.
OBSERVATION INDEX
- Zero-radius turns in structural cover
- Sediment concealment with raised eyes
- Undulatory pectoral propulsion on bottoms
03 / SPECIES
Representative species
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
Elongate goatfish
Pristigasteridae
elongate ilisha
Ilisha elongata
Botiidae
Elongate loach
Leptobotia elongata
Leiognathidae
Elongate ponyfish
Equulites elongatus
Gobiesocidae
Elongate shore eel
Alabes elongata
Apogonidae
Elongate siphonfish
Siphamia elongata
Acanthuridae
Elongate unicornfish
Naso lopezi
Cichlidae
Elongated eartheater
Gymnogeophagus mekinos
Labridae
ember parrotfish
Scarus rubroviolaceus
Engraulidae
Emblem anchovy
Stolephorus insignus
Gobiidae
Emerald coral goby
Paragobiodon xanthosoma
Gobiidae
Emery's pygmygoby
Trimma emeryi
Gobiidae
Emily’s shrimpgoby
Tomiyamichthys emilyae
Anthiadidae
Emma's basslet
Pseudanthias emma
Pomacanthidae
emperor angelfish
Pomacanthus imperator
Acanthuridae
epaulette surgeonfish
Acanthurus nigricauda
Pristigasteridae
Equatorial longfin herring
Opisthopterus equatorialis
Leiognathidae
Equulites berbis
Equulites klunzingeri
Pseudochromidae
Erdmann’s Dottyback
Pseudochromis erdmanni
Atherinidae
Estuarine hardyhead
Craterocephalus honoriae
Monacanthidae
Estuary filefish
Paramonacanthus tricuspis
Lutjanidae
Etelis bowen
Etelis boweni
Euclichthyidae
Eucla cod
Euclichthys polynemus
Osmeridae
eulachon
Thaleichthys pacificus
04 / FIELD NOTES
A closer look
What is the evolutionary difference between a ray and a flounder?
A ray is a cartilaginous fish flattened from top to bottom (dorsoventrally depressed) with eyes on top and gill slits on the underside; a flounder is a bony fish that lies on its side, whose eye migrates during larval development to make the body asymmetrical.
Why do disk-shaped fish like angelfish and discus have tall bodies?
A laterally compressed disc shape provides high vertical stability and exceptional turning agility, allowing fish to twist into narrow vertical crevices and maneuver between tangled roots or coral branches without losing control.