Somniosidae
knifetooth dogfish
Scymnodon ringens
FISH SPECIES
Sharks
Sharks are cartilaginous fishes with skeletons made primarily of cartilage. They include small bottom dwellers, open-ocean hunters and giant filter feeders such as the whale shark.
FISH ATLAS / FIELD GUIDESharksIN THIS CHAPTER01 / Characteristics02 / Lifestyle03 / Species04 / Field notes
SCROLL
01 / NATURAL HISTORY
Characteristics
Typical features include exposed gill slits, replaceable teeth and placoid scales that give the skin a tooth-like texture. Body form and feeding strategy vary across the major shark orders.
- 01Ground sharks
- 02Mackerel sharks
- 03Carpet sharks
02 / LIFESTYLE
Lifestyle
Shark locomotion and foraging strategies reflect adaptations across diverse marine niches. While active pelagic predators utilize obligate ram ventilation and cruise continuously using specialized caudal keels, many benthic species possess spiracles that allow stationary pumping while resting on the ocean floor. Electroreceptive ampullae of Lorenzini detect minuscule bioelectric fields emitted by buried prey during low-speed sweeps.
OBSERVATION INDEX
- Continuous cruising vs stationary rest
- Bioelectric tracking with ampullae
- Pelagic schooling and bottom hunting
03 / SPECIES
Representative species
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
knifetooth dogfish
Pentanchidae
Largenose catshark
Apristurus nasutus
Somniosidae
Largespine velvet dogfish
Scymnodon macracanthus
Dalatiidae
largetooth cookiecutter shark
Isistius plutodus
Centrophoridae
leafscale gulper shark
Centrophorus squamosus
Carcharhinidae
Lemon shark
Negaprion brevirostris
Scyliorhinidae
leopard catshark
Poroderma pantherinum
Hemiscylliidae
Leopard Epaulette Shark
Hemiscyllium michaeli
Triakidae
leopard shark
Triakis semifasciata
Pentanchidae
lined catshark
Halaelurus lineatus
Etmopteridae
lined lanternshark
Etmopterus bullisi
Etmopteridae
Lined lanternshark
Etmopterus dislineatus
Centrophoridae
little gulper shark
Centrophorus uyato
Somniosidae
little sleeper shark
Somniosus rostratus
Scyliorhinidae
Lizard catshark
Schroederichthys saurisqualus
Pentanchidae
lollipop cat shark
Cephalurus cephalus
Pentanchidae
Longfin catshark
Apristurus herklotsi
Centrophoridae
Longfin gulper shark
Centrophorus longipinnis
Lamnidae
Longfin mako
Isurus paucus
Pentanchidae
Longhead catshark
Apristurus longicephalus
Pentanchidae
Longnose catshark
Apristurus kampae
Triakidae
Longnose houndshark
Iago garricki
Squalidae
Longnose spurdog
Squalus blainville
Somniosidae
longnose velvet-shark
Centroselachus crepidater
04 / FIELD NOTES
A closer look
Must all sharks swim constantly to avoid suffocating?
No. Only certain open-ocean sharks rely on obligate ram ventilation. Many bottom-dwelling species (like nurse and carpet sharks) use spiracles and buccal pumping to breathe while resting stationary on the ocean floor.
How many teeth do sharks produce in a lifetime?
Shark teeth are arranged in conveyer-belt rows and continually shed as they wear down; an individual shark can produce thousands of functional teeth over its lifetime.
Is a whale shark dangerous to humans?
No. Despite reaching over 12 meters in length, whale sharks are gentle filter feeders that consume microscopic plankton, krill and small schooling fishes, posing no danger to divers.