Let's see, generally the common name "sharksucker" denotes members of the genus Echineis. These tend to be long and skinny, often with long stripes on their bodies.Scuba_Jenny:yeah, what is the difference?
Members of the genus Remora usually get tagged with the common name "remora". Remoras have deeper bodies than sharksuckers, and usually less distinctive markings. Basically they're shorter, fatter, and drabber.
The "whale sucker" and "marlin sucker" both are members of Remora also, but keep a bit of the "sucker" name with them. But being Remora, they retain the Remora body shape, not the sharksucker shape of Echeneis.
There are a couple of other genera also, Remorina being one. These like mantas, and are white. Love to see one of those babies.
Originally all members of this family were lumped into the genus Echineis, but now they're split into five genera. Eight species total. A lot of critters previously thought to be separate species have been combined.