Blenniidae
Lonely Blenny
Entomacrodus solus
FISH SPECIES
Long-bodied Fish
Explore fish with elongated, anguilliform or ribbon-like silhouettes, and learn how length changes locomotion and foraging.
FISH ATLAS / FIELD GUIDELong Bodied FishIN THIS CHAPTER01 / Characteristics02 / Lifestyle03 / Species04 / Field notes
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01 / NATURAL HISTORY
Characteristics
Elongated body plans reduce hydrodynamic drag, allow passage through tight apertures, and feature reduced or absent pelvic fins combined with extensive multi-vertebral muscular flexing systems.
- 01Anguilliform wave propulsion
- 02Crevice & conduit navigation
- 03Reduced appendages & low drag
02 / LIFESTYLE
Lifestyle
True eels swim via full-body anguilliform waves, sending lateral bends down their entire length to push against water, allowing them to reverse direction inside narrow subterranean burrows. Needlefish and pikes maintain a rigid elongated torso, keeping the body straight until their posterior fins and muscular caudal peduncle unleash sudden, explosive forward lunges.
OBSERVATION INDEX
- Full-body anguilliform undulation
- Reverse movement inside burrows
- Rigid body ambush alignment
03 / SPECIES
Representative species
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
Lonely Blenny
Hemiramphidae
Long billed half beak
Rhynchorhamphus georgii
Ophichthidae
Long bodied snake eel
Ophichthus shaoi
Paralepididae
Long light-organ barracudina
Lestidium longilucifer
Muraenidae
Long moray
Gymnothorax longinquus
Cyprinidae
Long pectoral-fin minnow
Macrochirichthys macrochirus
Cyprinidae
Long spiky-head carp
Luciobrama macrocephalus
Siluridae
Long-barbel sheatfish
Kryptopterus limpok
Ariidae
long-barbeled sea catfish
Bagre pinnimaculatus
Bagridae
Long-fatty finned mystus
Mystus singaringan
Gobiesocidae
Long-fin Butterfly Clingfish
Propherallodus longipterus
Siluridae
Long-fin glass catfish
Ompok pinnatus
Channichthyidae
Long-fingered icefish
Pagetodes antarcticus
Gempylidae
Long-finned escolar
Rexea antefurcata
Gobiidae
Long-finned goby
Valenciennea longipinnis
Ophichthidae
Long-finned worm eel
Scolecenchelys breviceps
Gobionidae
Long-nosed gudgeon
Microphysogobio longidorsalis
Trichonotidae
Long-rayed sand-diver
Trichonotus elegans
Syngnathidae
Long-snouted pipefish
Stigmatopora macropterygia
Liparidae
Long-tailed snailfsh
Paraliparis ruficometes
Chlopsidae
Long-toothed false moray
Boehlkenchelys longidentata
Stomiidae
Longbarb dragonfish
Flagellostomias boureei
Macrouridae
longbeard grenadier
Gadomus dispar
Macrouridae
longbeard grenadier
Ventrifossa macropogon
04 / FIELD NOTES
A closer look
Why do eels and morays lack pelvic fins?
Pelvic fins create hydrodynamic drag and easily catch on obstructions when navigating tight crevices, burrows and rock cracks. Over evolutionary time, appendages were reduced or lost in favor of continuous median fins.
How do elongated fish like gar and needlefish hunt?
Rather than undulate their whole bodies, they hold their long torsos completely straight to resemble floating sticks or debris, then unleash rapid lateral head snaps or tail bursts to impale unsuspecting prey on their toothed jaws.