This bird family houses small, insectivorous passerines, endemic to Australia and New Guinea. They are commonly known as Wrens, although they are unrelated to the true wrens from the Northern Hemisphere. Hybridization is documented in one genus, Malurus.

Several putative hybrids have been documented, including a possible Red-backed Fairywren (M. melanocephalus) x Superb Fairywren (M. cyaneus) in Queensland (Wilson, 1983) and White-winged Fairywren (M. leucopterus) x Splendid Fairywren at the Hart Lagoon (Haines, 2014).

One study described the hybrid zone between two subspecies of Variegated Fairy-wren (M. lamberti rogersi and M. l. assimilis) based on morphology (Ford & Johnstone, 1991).

A genomic analysis of another hybrid zone, between subspecies of the Red-backed Fairy Wren (M. melanocephalus), revealed differential introgression (Baldassarre et al., 2014). In addition, orange plumage spread across the hybrid zone due to sexual selection (Baldassarre & Webster, 2013), while song was resistant to introgression (Greig & Webster, 2013). Experiments suggest that male behavioural responses hinder the introgression of song, but allow for the introgression of plumage (Greig, Baldassarre & Webster, 2015).

References

Baldassarre, D. T. & Webster, M. S. (2013). Experimental evidence that extra-pair mating drives asymmetrical introgression of a sexual trait. Proceedings of the Royal Society B-Biological Sciences 280.

Baldassarre, D. T., White, T. A., Karubian, J. & Webster, M. S. (2014). Genomic and Morphological Analysis of a Semipermeable Avian Hybrid Zone Suggests Asymmetrical Introgression of a Sexual Signal. Evolution 68, 2644-2657.

Ford, J. R. & Johnstone, R. E. (1991). Hybridization between Malurus-Lamberti-Rogersi and Malurus-Lamberti-Assimilis in North-Western Australia. Emu 91, 251-254.

Greig, E. I., Baldassarre, D. T. & Webster, M. S. (2015). Differential rates of phenotypic introgression are associated with male behavioral responses to multiple signals. Evolution 69, 2602-2612.

Greig, E. I. & Webster, M. S. (2013). Spatial decoupling of song and plumage generates novel phenotypes between 2 avian subspecies. Behavioral Ecology 24, 1004-1013.

HAINES, P. (2014). Hybrid Fairywren at Hart Lagoon, River Murray, South Australia. South Australian Ornithologist, 39, 2..

Wilson, M. (1983). Apparent Hybridisation between two species of Fairy-wren. Sunbird, 13(2): 38-39.