Mongolian Gull: pale upperside, clear contrast between black primaries and pale blue-grey upperwing, strikingly white head, typically two quite large mirrors on P10 and P9.

• 蒙古银鸥:淡色的上翼面；黑色初级飞羽和淡蓝灰色上翼面间明显的对比；显著的白色头部；典型地在P10及P9上有二个相当大的翼镜.