Chordata · chordates
Megamouth shark
Megachasma pelagios
Megachasmidae · megamouth sharksIUCN: Least Concern

A rare, deep-dwelling filter-feeding shark first discovered in 1976.
Fun factFewer than 300 megamouths have ever been recorded.
- Waters
- Worldwide
- Depth zone
- Twilight zone, 200–1,000 m
- Diet
- Krill & plankton (filter feeder)
- Size
- Up to 5.5 m
Classification
Chordata › Chondrichthyes › Lamniformes › Megachasmidae
- Kingdom Animalia animals
- Many-celled organisms that eat other living things for energy (heterotrophs)
- Cells have no cell walls
- Most can move at some stage of life
- Clade Bilateria bilateral animals
- Body has a left and right side that mirror each other (bilateral symmetry)
- Head end with concentrated nerves; three tissue layers
- Includes about 99% of all living animal species
- Clade Deuterostomia deuterostomes
- In the embryo, the first opening becomes the anus and the mouth forms second
- Includes echinoderms and chordates
- Phylum Chordata chordates
- At some stage of life: a stiffening rod along the back (notochord)
- A hollow nerve cord along the back (dorsal)
- Slits in the throat (pharyngeal slits) and a tail past the anus
- Subphylum Vertebrata vertebrates
- A skull (cranium) protecting a brain
- Backbone or similar support around the nerve cord
- Includes fishes, amphibians, reptiles, birds, and mammals
- Infraphylum Gnathostomata jawed vertebrates
- Jawed vertebrates: jaws formed from gill arches
- Paired fins or limbs
- Includes all fishes except hagfish and lampreys, plus all tetrapods
- Class Chondrichthyes cartilaginous fishes
- Skeleton made of cartilage, not bone
- Skin covered in tooth-like scales (denticles)
- Teeth constantly replaced; males have claspers for mating
- Subclass Elasmobranchii sharks & rays
- Sharks and rays: five to seven separate gill slits on each side
- Many rows of replaceable teeth
- Clade Selachii sharks
- Sharks: gill slits on the sides of the head
- Pectoral fins not joined to the head
- Superorder Galeomorphii galeomorph sharks
- Sharks with an anal fin and five gill slits
- Includes most familiar sharks
- Order Lamniformes mackerel sharks
- Mackerel sharks: anal fin and two dorsal fins without spines
- Mouth reaches behind the eyes; no eyelid (nictitating membrane)
- Embryos feed on unfertilized eggs in the womb
- Family Megachasmidae megamouth sharks
- Megamouth sharks: huge mouth for filtering krill
- Genus Megachasma
- Species in the same genus are very close relatives and often look alike.
- Species Megachasma pelagios Megamouth shark
Closest relatives in the guide
- Basking shark Cetorhinus maximus same order
- Common thresher shark Alopias vulpinus same order
- Goblin shark Mitsukurina owstoni same order
- Great white shark Carcharodon carcharias same order
- Porbeagle Lamna nasus same order
- Sand tiger shark Carcharias taurus same order
- Shortfin mako Isurus oxyrinchus same order
- Atlantic angel shark Squatina dumeril same class