Wikipedia
The Mancallinae were a group of prehistoric flightless auk relatives that lived on the Pacific coast of today's California and Mexico from the late Miocene epoch to the early Pleistocene (ranging from at least 7.4 million to 470 thousand years ago). They are sometimes collectively referred to as Lucas auks after the scientist who described the first species, Frederic Augustus Lucas.
They had evolved along somewhat similar lines as the great auk, their North Atlantic ecological counterpart, but their decidedly stubbier wings were in some aspects more convergent with penguins. Compared with the subarctic great auk, they were also smaller (see also: Bergmann's Rule): Praemancalla species have been estimated to have weighed about 3 kg. Most Mancalla forms weighed somewhat less (about 2.4 kg), with M. milleri being a smaller (1.65 kg) and M. emlongi a much larger bird (3.8 kg) than the rest. The last species thus stood around 55–60 cm high in life. The largest species, Miomancalla howardi, was the largest charadriiforme of all time.