Pomacentridae
Indonesian damsel
Pomacentrus melanochir
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.
Indonesian damsel
Acanthuridae
Indonesian sawtail
Prionurus chrysurus
Bothidae
Intermediate flounder
Asterorhombus intermedius
Trichiuridae
intermediate scabbardfish
Aphanopus intermedius
Centropomidae
Ira’s snook
Centropomus irae
Apogonidae
Iridescent cardinalfish
Pristiapogon kallopterus
Bagridae
Irrawaddy mystus
Hemibagrus microphthalmus
Pomacentridae
Island major
Stegastes arcifrons
Carangidae
Island trevally
Ferdauia orthogrammus
Epinephelidae
itajara
Epinephelus itajara
Pseudochromidae
Jaguar dottyback
Pseudochromis moorei
Pseudochromidae
Jamal's dottyback
Manonichthys jamali
Gobiidae
Janet's shrimpgoby
Tomiyamichthys eyreae
Pomacanthidae
Japanese angelfish
Centropyge interrupta
Paralepididae
Japanese barracudina
Lestrolepis japonica
Priacanthidae
Japanese bigeye
Pristigenys niphonia
Chaetodontidae
Japanese butterflyfish
Chaetodon nippon
Pomacentridae
Japanese chromis
Chromis mirationis
Dorosomatidae
Japanese gizzard shad
Nematalosa japonica
Engraulidae
Japanese grenadier anchovy
Coilia nasus
Monacanthidae
Japanese leatherjacket
Paramonacanthus japonicus
Bothidae
Japanese lefteye flounder
Arnoglossus japonicus
Apogonidae
Japanese Naked-cardinalfish
Gymnapogon japonicus
Labridae
Japanese parrotfish
Calotomus japonicus
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.