Mancallinae is an extinct subfamily of prehistoric flightless alcids 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 470,000 years ago). They are sometimes collectively referred to as Lucas auks after the scientist who described the first species, Frederic Augustus Lucas. Description 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. Evolution and classification In a 2011 paper, N. Adam Smith published a review and revision of the Mancallinae. Smith defined Mancallinae as the clade containing Mancalla, Miomancalla, their common ancestor and all its descendants. A summary of his results follows. Pan-Alcidae Smith, 2011 Mancallinae L.Miller, 1946 Mancalla Lucas, 1901 Mancalla californiensis Lucas, 1901 Mancalla cedrosensis Howard, 1971 Mancalla lucasi Smith, 2011 Mancalla vegrandis Smith, 2011 Miomancalla Smith, 2011 Miomancalla howardi (Smith, 2011) Miomancalla wetmorei (Howard, 1976) The following species could not be identified as unquestionable mancallines, and have been assigned to Pan-Alcidae incertae sedis. They may be mancallines, or more closely related to true auks. Alcodes ulnulus Howard, 1968 Mancalla diegensis Miller, 1937 Mancalla milleri Howard, 1970 The following species could not be differentiated from other recognized species of mancallines (see above), and have been assigned to Mancallinae incertae sedis. Mancalla emlongi Olson, 1981 Praemancalla lagunensis Howard, 1966 The mancallines probably evolved from proto-puffins, which must have been birds not dissimilar to the rhinoceros auklet. Accordingly, their status as a subfamily has been questioned as this would make the Alcinae (true auks) paraphyletic. However, the mancallines were a very distinct and unique evolutionary lineage and are thus usually retained as a subfamily. They must have diverged from flying ancestors during the mid-Miocene, roughly 15 mya. Alcodes is known from a single ulna found in Late Miocene (Clarendonian, 9–12 mya) deposits at Laguna Hills, California.