Nannus

Nannus
Eurasian Wren (Nannus troglodytes)
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Troglodytidae
Genus: Nannus
Billberg, 1828
Type species
Motacilla troglodytes
Linnaeus, 1758
Species

See text

Nannus is a genus of passerine birds in the wren family. Of the three species in this genus, two occur in North America, while the third (the only member of the wren family native to the Old World) is distributed across Eurasia and North Africa. All species in the genus were formerly placed in the genus Troglodytes.

Etymology

The genus Nannus was described in 1828 by the Swedish scientist Gustaf Johan Billberg. The genus name is derived from the Ancient Greek word ναννος (nannos), meaning "dwarf".

Description

Oberholser (1919) distinguished Nannus from Troglodytes by its relatively short tail, measuring less than three-quarters of the wing length; its slender, flattened bill with a nearly straight culmen; and its narrow, slit-like nostrils, largely covered by thin, overhanging membranes.

Systematics

In the early 20th century, Nannus was often recognized as a genus distinct from Troglodytes. However, Hellmayr (1934) considered the morphological differences between the two genera insufficient to justify their separation, pointing in particular to the existence of species with intermediate characteristics. He therefore merged Nannus into Troglodytes, a treatment that subsequently became widely adopted.

Later, Rice et al. (1999) found that Troglodytes, as then broadly defined, was paraphyletic, with the species traditionally placed in Nannus distantly related to the remaining members of Troglodytes. They consequently proposed reinstating Nannus as a distinct genus. Subsequent molecular phylogenetic studies by Barker (2017) and Imfeld et al. (2024) provided further support for this separation, with the latter recovering Nannus as the sister group to Cistothorus. The genus was recognized by the American Ornithological Society and AviList in 2026.

The phylogenetic tree below is from Imfeld et al. (2024).

Nannus

Winter wren − Nannus hiemalis

Pacific wren − Nannus pacificus

Eurasian wren − Nannus troglodytes

Species

The genus contains 3 species:

ImageCommon nameScientific nameDistribution
Winter wrenNannus hiemalisbreeds from northeastern British Columbia eastward to Newfoundland (northwestern to northeastern Canada), southward to Wisconsin to southern Ontario, and in the Appalachians to far northeastern Georgia; winters in the southern half of the eastern USA to northeastern Texas, the Gulf coast, and northern Florida
Pacific wrenNannus pacificusFrom southern and western Alaska, including the Aleutian and Pribilof Islands, southward to southwestern Alberta (southwestern Canada) in northern Rocky Mountains to southern Idaho and western Montana, and the USA along the Pacific coast and ranges to central California, with an isolated population in central Arizona and possibly in western South Dakota (Black Hills)
Eurasian wrenNannus troglodytesFrom Iceland, North Atlantic islands, and British Isles eastward to Kamchatka and Japan, and southward to northern Africa, Levant, Caucasus, Himalayas, southern China, and Taiwan

References

  1. 1 2 Jobling, James A. "The Key to Scientific Names". Birds of the World. Cornell Lab of Ornithology. Retrieved 24 October 2026.
  2. 1 2 Fjeldså, Jon; Christidis, Les; Ericson, Per G. P. (2020). The largest avian radiation: the evolution of perching birds, or the order Passeriformes. Barcelona: Lynx edicions. pp. 241–244. ISBN 978-84-16728-33-6.
  3. ↑ Billberg, Gustaf Johan (1828). Synopsis faunae Scandinaviae (in Latin). Vol. 1. Holmiae: Caroli Deleen. p. 57. doi:10.5962/bhl.title.69294.
  4. ↑ Oberholser, Harry C. (1919). "Notes on the wrens of the genus Nannus Billberg". Proceedings of the United States National Museum. 55 (2265): 224. doi:10.5479/si.00963801.55-2265.223.
  5. ↑ American Ornithologists' Union (1931). Check-list of North American birds (4th ed.). Lancaster, Pennsylvania: American Ornithologists' Union. p. 242. doi:10.5962/bhl.title.6394.
  6. ↑ Hellmayr, Carl Eduard (1934). Catalogue of birds of the Americas and the adjacent islands in Field Museum of Natural History. Field Museum of Natural History, Zoological Series. Vol. 13. Chicago: Field Museum of Natural History. p. 216.
  7. ↑ American Ornithologists' Union (1945). "Twentieth Supplement to the American Ornithologists' Union Check-list of North American Birds". The Auk. 62 (3): 436–449. doi:10.2307/4079864.
  8. ↑ Rice, Nathan H.; Peterson, A. Townsend; Escalona-Segura, Griselda (1999). "Phylogenetic patterns in montane Troglodytes wrens". The Condor. 101 (2): 446–451. doi:10.2307/1370013.
  9. ↑ Barker, F. Keith (2017). "Molecular phylogenetics of the wrens and allies (Passeriformes: Certhioidea), with comments on the relationships of Ferminia". American Museum Novitates (3887): 1–27. doi:10.1206/3887.1.
  10. 1 2 Imfeld, Tyler S.; Barker, F. Keith; Vázquez-Miranda, Hernán; Chaves, Jaime A.; Escalante, Patricia; Spellman, Garth M.; Klicka, John (2024). "Diversification and dispersal in the Americas revealed by new phylogenies of the wrens and allies (Passeriformes: Certhioidea)". Ornithology. 141 (2): 1–15. doi:10.1093/ornithology/ukae007.
  11. ↑ Chesser, R. Terry; Billerman, Shawn M.; Burns, Kevin J.; Cicero, Carla; Dunn, Jon L.; Hernández-Baños, Blanca E.; Johnson, Oscar; Mason, Nicholas A.; Rasmussen, Pamela C. (2026-10-20). "Sixty-seventh Supplement to the American Ornithological Society's Check-list of North American Birds". Ornithology. doi:10.1093/ornithology/ukag037.
  12. 1 2 AviList Core Team. 2026. AviList: The Global Avian Checklist, v2026. https://doi.org/10.2173/avilist.v2026