Identifying Ocean Sunfish (Molas)
Many people mistakenly identify any sunfish as Mola mola. However, there are five members of that family. If seen well, they aren't hard to separate.
Ocean Sunfish Mola mola
This is the most widespread member of the family, found in both tropical and subtropical waters of every ocean. Note that the face is lumpy in profile, with a protrusion in front of the eye and at the mouth. The clavus (tail) is wrinkled, with a rounded crease between the fins. Photo by Ilse Reijs and Jan-Noud Hutten.
Short Sunfish Mola alexandrini (or M. ramseyi)
This fish is only found in the southern oceans. It is very similar to the Ocean Sunfish, but note that the clavus (tail) is smooth without wrinkles, and it lacks a forehead bump when seen in profile. Photo by Peter.
Hoodwinker Sunfish Mola tecta
This fish is only known from the southern oceans. It is very similar to the Ocean Sunfish, but has a slightly pointed snout, lacks a forehead bump, has a slight notch in the middle of the clavus (tail), and grows larger. Public domain photo by Cesar Villarroel, Explorasub.
Sharptail Sunfish Masturus lanceolatus
This species can be found globally in tropical and temperate seas. Its appearance is somewhat like the Ocean Sunfish, but note the projection on the clavus (tail) and smoothly rounded head profile. Photo by Hectonichus.
Slender Sunfish Ranzania laevis
This species can be found globally in tropical and temperate seas, though it is seldom seen. The body shape and pattern is distinctive. Public domain photo from NOAA.