From a distance, these small ducks appear to be just plain brown, but when observed closely, you will notice the buff spots or “marbles” for which this species is named for. The sexes are similar, with hens having a yellowish patch at the base of the bill. Males seem to have a larger head than hens, due to a crest that is used when courting hens. Both sexes lack the metallic wing speculum seen in other teals.