Alosidae
European pilchard
Sardina pilchardus
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.
European pilchard
Apogonidae
Evermann's cardinalfish
Zapogon evermanni
Stomiidae
Exotic snaggletooth
Eupogonesthes xenicus
Labridae
exquisite wrasse
Cirrhilabrus exquisitus
Gobiidae
Eyebar spiny goby
Asterropteryx spinosa
Lethrinidae
Eyebrowed large-eye bream.
Gymnocranius superciliosus
Cyprinidae
Eyeless golden-line fish
Sinocyclocheilus anophthalmus
Anomalopidae
eyelight fish
Photoblepharon palpebratum
Apogonidae
Eyeshadow Cardinalfish
Pristiapogon exostigma
Pomacentridae
Eyespot Damselfish
Pomacentrus andamanensis
Acanthuridae
eyestripe surgeonfish
Acanthurus dussumieri
Pempheridae
Fahal sweeper
Pempheris wilsoni
Monacanthidae
Faintstripe filefish
Paramonacanthus pusillus
Clupeidae
Falkland sprat
Sprattus fuegensis
Pseudochromidae
False Bandit Dottyback
Pseudochromis colei
Pseudochromidae
False midnight dottyback
Manonichthys winterbottomi
Dorosomatidae
false pilchard
Harengula clupeola
Acestrorhamphidae
False rummynose tetra
Petitella georgiae
Characidae
false silver tetra
Tetragonopterus chalceus
Lactariidae
false trevally
Lactarius lactarius
Pomacentridae
false-eye sergeant
Abudefduf sparoides
Bothidae
Fan flounder
Parabothus coarctatus
Sparidae
Fanged seabream
Sparidentex jamalensis
Anoplogastridae
fangtooth
Anoplogaster cornuta
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.