The Werewolf is the only lycanthrope known to exist everywhere in Tamriel. They are known to have a connection with the Daedric Lord Hircine, and are often described as his hounds. They are the second most common lycanthrope in Skyrim behind Werebears.
The Circle, an elite group of warriors within The Companions, is comprised of werewolves. Lycanthropy is passed down to new members through a blood ritual upon their admittance into the Circle. Werewolves carry a weakness of Silver Weapons.
Weresharks are believed to roam the oceans around Tamriel. Their existence has never been confirmed as only a rumor of their existence is ever mentioned in the Daggerfall text: "On Lycanthropy" and even then the author, Varnard Karessen, only briefly mentions that he has heard of these lycanthropes, and nothing more.