The Monarch Flycatchers comprise a family of passerine birds which includes Boatbills, Paradise Flycatchers and Magpie Larks. They occur across sub-Saharan Africa, south-east Asia, Australia and a few Pacific Islands. Hybridization has been documented in one genus, Terpsiphone.
Terpsiphone
Chapin (1948) discusses hybridization dynamics between Red-bellied Paradise Flycatcher (T. rufiventer), Rufous-vented Paradise Flycatcher (T. rufocinerea) and African Paradise Flycatcher (T. viridis) in Africa.
In Northern Congo, hybridization between Red-bellied Paradise Flycatcher (T. rufiventer) and Bates’ Paradise Flycatcher (T. batesi) is common. About 35% of the territories are held by hybrids (Dowsett-Lemaire, 1999).
Monarcha
A study investigating the evolutionary history of the Monarcha castaneiventris species complex showed that two melanic populations of the subspecies ugiensis have independent origins. In addition, both populations have interbred with another population (subspecies megarhynchus) on the larger island of Makira (Cooper & Uy, 2017; Uy et al., 2016).

Two subspecies of Monarcha castaneiventris: the chestnut-bellied megarhynchus and the entirely black ugiensis
References
Chapin, J. P. (1948). Variation and hybridization among the paradise flycatchers of Africa. Evolution, 111-126.
Cooper, E. A., & Uy, J. A. C. (2017). Genomic evidence for convergent evolution of a key trait underlying divergence in island birds. Molecular Ecology, 26(14), 3760-3774. doi: 10.1111/mec.14116
Dowsett-Lemaire, F. (1999). Hybridization in paradise flycatchers (Terpsiphone rufiventer, T-batesi and T-viridis) in Ondzala National Park, Northern Congo. Ostrich 70, 123-126.
Uy, J. A. C., Cooper, E. A., Cutie, S., Concannon, M. R., Poelstra, J. W., Moyle, R. G., & Filardi, C. E. (2016). Mutations in different pigmentation genes are associated with parallel melanism in island flycatchers. Proceedings of the Royal Society B-Biological Sciences, 283(1834), 20160731.
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