Diagnoses of hybrid hummingbirds (Aves: Trochilidae) .1. Characterization of Calypte anna x Stellula calliope and the possible effects of egg volume on hybridization potential

Abstract

Plumage pattern, plumage color, and external morphology of two specimens of hybrid hummingbird (Calypte anna x Stellula calliope) are described. The parental species differ substantially in size, and the hybrids are similar to the averages of character means of the parental species. Expression of parental plumage characters in the hybrids varies, particularly the color and configuration of the frontlet and gorget. The possible effects of egg volume on hybridization potential are discussed.