Subspecies
Brachyramphus marmoratus (Sibley and Monroe 1990, 1993) has been split into Marbled Murrelet (Brachyramphus marmoratus) and Long-billed Murrelet (Brachyramphus perdix) following AOU (1998).
Considered by some authors to be a subspecies of Marbled Murrelet (Brachyramphus marmoratus).