General features White underparts, brownish grey back. Nape and crown pale grey, with a dark eye stripe and a pale supercilium, slightly visible. Black flight feathers and tail. X. cinereus and X. irupero are similar: the first one is much darker on upperparts, with black malar stripe and orange iris; the second one is much paler, almost completely white (only with black on flight feathers and extreme of the tail).
