Leucismo parcial en el papamoscas negro (Sayornis nigricans): primer registro para México

Leucism is the partial loss of pigmentation. It can be expressed totally or partially in the plumage. We recorded an adult individual of the Black Phoebe ( Sayornis nigricans ) with partial leucism. On 22 July 2017 we observed this tyranid at the northwestern side of Puebla near a body of water in a forestry management property called Mesa Chica, Ahuazotepec. This is the first report of partial leucism for this species in Mexico. Due to the increase of reports on aberrations in avian plumage coloration it is desirable to carry out comparative studies to determine the factors that cause these anomalies.