African Sacred Ibis (Threskiornis aethiopicus) Science Article 1
Sacred Ibis Threskiornis aethiopicus is closelyrelated to both Black-headed Ibis T. melanocephalus(from the Indian subcontinent) andAustralian White Ibis T. molucca (which breedsin Australia, New Guinea and some nearbyislands)-to the point that they are sometimestreated as one species, T. aethiopicus. However,they are generally regarded as three distinctspecies forming a superspecies (eg del Hoyo etal. 1992).
Pierre Yesou and Philippe Clergeau, Birding World 18 (12): 517-526