Belongs within: Ardeidae.
The genus Ixobrychus is generally recognised as including the smaller bitterns, relatively short-necked, stout members of the heron family. However, recent phylogenetic analyses (e.g. Jetz et al. 2012) suggest that the larger bitterns of the genus Botaurus may also be nested within the clade formed by the Ixobrychus species. The smaller bitterns are often more boldly coloured than the Botaurus species which are uniformly streaked brown.
<==Ixobrychus Billberg 1828 [=Ardetta Gray 1842; incl. Ardeola Bonaparte 1852 non Boie 1822, Nannocnus Stejneger 1887] CC10
| i. s.: I. novaezelandiae (Purdie 1871) [=Ardeola novaezelandiae, I. minutus novaezelandiae] CC10
| I. sturmii JT12
|--I. involucris BKB15
`--+--+--I. exilis (Gmelin 1789) BKB15, CS77 [=Ardea exilis CS77, *Ardeola exilis CC10]
| | |--I. e. exilis E52
| | `--I. e. erythromelas E52
| `--Botaurus Stephens in Shaw 1819 BKB15, CC10 [Botaurini]
| | i. s.: B. poiciloptilus (Wagler 1827) CC10 (see below for synonymy)
| |--*B. stellaris (Linnaeus 1758) CC10, BKB15, M02 (see below for synonymy)
| | |--B. s. stellaris [incl. B. stellaris orientalis Buturlin 1908] CS77
| | `--B. s. capensis (Schlegel 1863) CS77
| `--+--B. lentiginosus Montagu 1813 BKB15, CS77 [=Ardea lentiginosa CS77]
| `--B. pinnatus BKB15
`--+--I. eurhythmus (Swinhoe 1873) BKB15, CS77 [=Ardetta eurhythma CC10, *Nannocnus eurhythmus CC10]
|--+--*I. minutus (Linnaeus 1766) CC10, BKB15, CC10 [=Ardea minuta CC10, *Ardetta minuta CC10]
| | |--I. m. minutus CC10
| | |--‘Ardea’ m. australis [incl. Ardeola podiceps] S66
| | |--I. m. dubius Mathews 1912 (see below for synonymy) CC10
| | `--I. m. payesii (Hartlaub 1858) CS77
| `--I. sinensis BKB15
`--+--I. cinnamomeus BKB15
`--I. flavicollis (Latham 1790) BKB15, CC10 [=Ardea flavicollis WS48, Dupetor flavicollis CC10]
|--I. f. flavicollis WS48
`--‘Dupetor’ f. gouldi (Bonaparte 1855) (see below for synonymy) WS48
Botaurus poiciloptilus (Wagler 1827) CC10 [=Ardea poiciloptila CC10, Ardea poeciloptera Finsch 1870 CC10, A. poiceloptera Hutton 1871 CC10, Botaurus poecilopterus CC10, B. poeciloptilus CC10, B. stellaris poiciloptilus CC10; incl. B. australis Gould 1848 CC10, B. poiciloptilus maorianus Iredale & Mathews 1926 CC10, B. poiciloptilus mathewsi Hachisuka 1931 CC10, B. melanotus Gray in Dieffenbach 1843 non Brehm 1842 CC10, B. poiciloptilus melanotus CC10, B. poiciloptilus westraliensis Mathews 1912 WS48]
*Botaurus stellaris (Linnaeus 1758) CC10, BKB15, M02 [=Ardea stellaris CC10; incl. Nycticorax fenensis Friant 1950 M02]
‘Dupetor’ flavicollis gouldi (Bonaparte 1855) [=Ardetta gouldi; incl. Ardeiralla flavicollis disneyi Mathews 1912] WS48
Ixobrychus minutus dubius Mathews 1912 [incl. I. minutus alisteri Mathews 1913, Ardea pusilla Vieillot 1817 non Statius Müller 1776, Ardetta pusilla, Ixobrychus minutus queenslandicus Mathews 1914, I. minutus victoria Mathews 1915] CC10
*Type species of generic name indicated
REFERENCES
[BKB15] Burleigh, J. G., R. T. Kimball & E. L. Braun. 2015. Building the avian tree of life using a large-scale, sparse supermatrix. Molecular Phylogenetics and Evolution 84: 53–63.
[CC10] Checklist Committee (OSNZ). 2010. Checklist of the Birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica 4th ed. Ornithological Society of New Zealand and Te Papa Press: Wellington.
[CS77] Cramp, S., & K. E. L. Simmons (eds) 1977. Handbook of the Birds of Europe, the Middle East and North Africa: The Birds of the Western Palaearctic vol. 1. Ostrich to Ducks. Oxford University Press: Oxford.
[E52] Eisenmann, E. 1952. Annotated list of birds of Barro Colorado Island, Panama Canal Zone. Smithsonian Miscellaneous Collections 117 (5): 1–62.
[JT12] Jetz, W., G. H. Thomas, J. B. Joy, K. Hartmann & A. Ø. Mooers. 2012. The global diversity of birds in space and time. Nature 491: 444–448.
[M02] Mlíkovský, J. 2002. Cenozoic Birds of the World. Part 1: Europe. Ninox Press: Praha.
[S66] Schlegel, H. 1866. Communication from, on mammals and birds collected in Madagascar. Proceedings of the Zoological Society of London 1866: 419–426.
[WS48] Whittell, H. M., & D. L. Serventy. 1948. A systematic list of the birds of Western Australia. Public Library, Museum and Art Gallery of Western Australia, Special Publication 1: 1–126.
Last updated: 1 December 2021.