Eurypygimorphae

Eurypygimorphae Temporal range: Early Eocene–present PreЄ Є O S D C P T J K Pg N
Top: white-tailed tropicbird (Phaethontiformes) Bottom: sunbittern (Eurypygiformes)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Clade:	Passerea
Clade:	Eurypgimorphae Fürbringer, 1888
Orders
Phaethontiformes Eurypygiformes

Eurypygimorphae is a clade of birds that contains the orders Phaethontiformes (tropicbirds) and Eurypygiformes (kagu and sunbittern) recovered by genome analysis^[1] the relationship was first identified in 2013 based on their nuclear genes.^[2] Historically these birds were placed at different parts of the tree, with tropicbirds in Pelecaniformes and the kagu and sunbittern in Gruiformes, though in the last decade various genetic analysis had found in the almost obsolete clade Metaves of uncertain placement within that group.^[3][4] Their sister taxon is possibly Aequornithes.^[1]

References

1. Jarvis, E.D.; et al. (2014). "Whole-genome analyses resolve early branches in the tree of life of modern birds". Science. 346 (6215): 1320–1331. doi:10.1126/science.1253451. PMC 4405904. PMID 25504713.
2. Yuri, Tamaki; Kimball, Rebecca; Harshman, John; et al. (2013). "Parsimony and Model-Based Analyses of Indels in Avian Nuclear Genes Reveal Congruent and Incongruent Phylogenetic Signals". Biology. 2 (1): 419–444. doi:10.3390/biology2010419.
3. Ericson, P. G.P; Anderson, C. L; Britton, T.; Elzanowski, A.; Johansson, U. S; Kallersjo, M.; Ohlson, J. I; Parsons, T. J; Zuccon, D.; Mayr, G. (2006). "Diversification of Neoaves: integration of molecular sequence data and fossils". Biology Letters. 2 (4): 543–547. doi:10.1098/rsbl.2006.0523. PMC 1834003. PMID 17148284.
4. Hackett, S. J.; Kimball, R. T.; Reddy, S.; et al. (2008). "A Phylogenomic Study of Birds Reveals Their Evolutionary History" (PDF). Science. 320 (5884): 1763–1768. doi:10.1126/science.1157704. PMID 18583609.