It is presently noted that the HD 82558 chromospherically active star is a young and rapidly rotating K2 V single BY Draconis variable with very strong far-UV emission features and an H-alpha line filled to the continuum level by emission. HD 82558 has constant velocity and is not a member of the Hyades Supercluster. Its light curve behavior, which appears to have been stable for several hundred rotation cycles, is reminiscent of that of the young, rapidly rotating, single K V variable H II 1883 in the Pleiades; this stability may be characteristic of young, single, chromospherically active stars.
Fekel, F.C.; Bopp, B.W.; Africano, J.L.; Goodrich, B.D.; Palmer, L.H.; Quingley, R.; Simon, T. "Chromospherically active stars. II. HD 82558, a young single BY Draconis variable." Astronomical Journal, Vol. 92, p. 1150-1154 (1986)