Badidae
Purpur Dario
Dario hysginon
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.
Purpur Dario
Cyprinidae
Putao Baril
Opsarius putaoensis
Cyprinidae
Putitor mahseer
Tor putitora
Badidae
Pyema Badis
Badis pyema
Antennariidae
Pygmy anglerfish
Antennatus linearis
Labridae
pyjama
Pseudocheilinus hexataenia
Pseudochromidae
Pyle's dottyback
Pseudochromis pylei
Chaetodontidae
Pyramid butterflyfish
Hemitaurichthys polylepis
Pomacanthidae
queen angelfish
Holacanthus ciliaris
Gobiidae
Queensland dwarfgoby
Eviota queenslandica
Histiophrynidae
Queensland frogfish
Histiophryne maggiewalker
Labridae
Quoy's parrotfish
Scarus quoyi
Chaetodontidae
Raccoon butterflyfish
Chaetodon lunula
Pristigasteridae
Raconda
Raconda russeliana
Scorpaenidae
Radial firefish
Pteropterus radiatus
Synanceiidae
Radial stingfish
Minous radiatus
Labridae
Raggedfin parrotfish
Chlorurus rhakoura
Pempheridae
Rahah sweeper
Parapriacanthus rahah
Lebiasinidae
Rainbow copella
Copella vilmae
Opistognathidae
Rainbow jawfish
Opistognathus evermanni
Carangidae
rainbow runner
Elagatis bipinnulata
Osmeridae
rainbow smelt
Osmerus mordax
Salmonidae
Rainbow trout
Oncorhynchus mykiss
Chaetodontidae
Rainford's butterflyfish
Chaetodon rainfordi
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.