Report of bilateral gynandromorphy in a Green Honeycreeper ( Chlorophanes spiza ) from Colombia

Abstract

We report recent sightings, substantiated by color photographs and a short video, of a bilateral gynandromoph of the Green Honeycreeper ( Chlorophanes spiza ) from Villamaría, in the department of Caldas, Colombia. The bird exhibited typical male plumage on its right side and female plumage on the left. It was present for at least 21 months, and its behavior largely matched that of other wild Green Honeycreepers, although it often waited until they were gone before feeding on fruit that was put out daily by the property owners. We provide a comprehensive list and review of previous records of passerine bilateral gynandromorphy, noting which sex’s plumage occurred on the left side. We observe that female plumage is possible on either side, supporting the double-fertilization model of bilateral gynandromorphy.

Keywords

• gynandromorph
• plumage
• sex determination
• sex differences
• sexual dimorphism