Des Murs's wiretail

Des Murs's wiretail
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Furnariidae
Genus: Sylviorthorhynchus
Species:
S. desmurii
Binomial name
Sylviorthorhynchus desmurii
Gay, 1845

Des Murs's wiretail (Sylviorthorhynchus desmurii) is a small passerine bird of southern South America which belongs to the ovenbird family Furnariidae. Molecular phylogenetics places it within the Synallaxinae and indicates that the genus diverged from the Leptasthenura about 14-15 million years ago.[2]

Taxonomy

Des Murs's wiretail was illustrated and given the binomial name Sylviorthorhynchus desmurii by the French naturalist Claude Gay in 1845.[3][4][5] The specific epithet was chosen to honour the French ornithologist Marc Athanase Parfait Œillet des Murs.[6] The species is monotypic: no subspecies are recognised.[7]

Description

It is 24 centimetres (9.4 in) long, with the very long tail accounting for about two-thirds of this, but weighs as little as 10 grams (0.35 oz).[8] The tail consists of just six feathers which are very narrow and filament-like: so few rectrices are elsewhere seen only in the emu-wrens of Australia.[9] The two central feathers are greatly elongated while the two outer feathers are very short. The plain plumage is reddish-brown above, paler on the underparts. There is a pale stripe above the eye. The bird is small and rounded with a very fine bill. The song is fast and high-pitched.

Distribution and habitat

It is found in western Argentina from Santa Cruz Province north to San Juan and in southern and central Chile from northern Magallanes to Valparaíso Region. It inhabits dense thickets of Chusquea bamboo within cool temperate rainforests, occurring from sea-level up to 1,200 metres, but also can occur in early-successional shrublands of highly shade-tolerant Myrtaceae species, chiefly Amomyrtus.[10] Des Murs's wiretail is also known to occur in dense weedy thickets of plants like gorse over the northern extremity of its range.[10] Even in undisturbed rainforests, however, wiretails use only the low-level shrub and bamboo layer for foraging, never flying higher than 3 metres (10 ft) above the ground.

Behaviour and ecology

It is very shy and difficult to see, being completely unable to enter areas without dense vegetative overstoreys,[11] and cannot typically use corridors smaller than 25 m (80 ft) or fly further than 50 m (160 ft) between patches of suitable habitat.[12]

When encountered Des Murs's wiretail can easily be mistaken for a mouse. It has the unique ability among birds to curl up its long tail into a ball when alarmed.[8]

The ball-shaped nest is made of plant fibres and built amongst vegetation close to the ground. Both partners are highly territorial with a territory size of around 1 ha (2.5 acres) per pair; however, pairs in territories smaller than 20 ha (49 acres) are seldom successful at nesting.[10] This territory and the nest site are defended vigorously against conspecifics with a distinctive territorial song,[12] and it is possible that the long tail is used by both sexes as an means of choosing a mate,[13] though no actual tests have been used to determine how wiretails find a mate.

As is typical for south temperate insectivorous birds, during the breeding season of October to February Des Murs's wiretail lays a clutch of two to four eggs,[12] but for the bird's mass these are about the largest eggs of any passerine bird. At 20.5 mm (0.8 in) long and 15.8 mm (0.6 in) wide,[8] they weigh twice as much as expected for a 10 gram passerine[14] and a clutch of four weighs more than the adult female - a feat equalled only by much more fecund kinglets. Little is known about incubation, fledging periods, or postfledging parental care due to the very secretive nature of the species.

References

  1. ^ BirdLife International (2018). "Sylviorthorhynchus desmurii". IUCN Red List of Threatened Species. 2018: e.T22702150A130272791. doi:10.2305/IUCN.UK.2018-2.RLTS.T22702150A130272791.en. Retrieved 28 September 2024.
  2. ^ Gonzalez, J. & M. Wink (2008) Phylogenetic position of the monotypic Des Murs’ Wiretail (Sylviorthorhynchus desmursii, Aves: Furnariidae) based on mitochondrial and nuclear DNA. Journal of Ornithology 149(3):393-398 doi 10.1007/s10336-007-0251-0
  3. ^ Gay, Claude (1845). Historia fisica y politica de Chile. Atlas. Vol. 2. Paris: E. Thunot y ca. Plate 3.
  4. ^ Gay, Claude (1847). Historia fisica y politica de Chile. Zoologica. Vol. 1. Paris: En casa del autor. p. 316.
  5. ^ Gregory, Steven; Dickinson, Edward (2012). "An assessment of three little-noticed papers on avian nomenclature by G. N. Kashin during 1978-1982". Zootaxa. 3340: 44-58 [48-49]. doi:10.11646/zootaxa.3340.1.3.
  6. ^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 134. ISBN 978-1-4081-2501-4.
  7. ^ Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (July 2023). "Ovenbirds, woodcreepers". IOC World Bird List Version 13.2. International Ornithologists' Union. Retrieved 28 October 2023.
  8. ^ a b c Johnson, Alfredo William (author) and Goodall, J.D. (illustrator); The birds of Chile and adjacent regions of Argentina, Bolivia, and Peru, Volume II; pp. 171-173.
  9. ^ Sibley, Charles Gald and Alquist, John E.; Phylogeny and Classification of the Birds: A Study in Molecular Evolution; p. 576. ISBN 0300040857
  10. ^ a b c Diáz, Iván A., Armesto, Juan J. and Willson, Mary F.,“Mating success of the endemic Des Murs’ Wiretail (Sylviorthorhynchus desmursii, Furnariidae) in fragmented Chilean rainforests”[permanent dead link‍]
  11. ^ Sieving, Katharyn E, Willson, Mary F. and de Santo, Toni L.; “Defining Corridor Functions for Endemic Birds in Fragmented South-Temperate Rainforest”
  12. ^ a b c Diáz, Iván A., Willson, Mary F., Gehee, Steven M.C. & Armesto, Juan J.; “Observaciones Sobre La Biologia y Conservación del Colilarga (Sylviorthorhynchus desmursii, Furnariidae) en la Isla de Chiloé, Chile” Archived 2016-03-04 at the Wayback Machine
  13. ^ See Moreno, Juan, Merino, Santiago, Lobato, Elisa, Rodríguez-Gironés, Miguel A. and Vásquez Rodrigo A.; “Sexual dimorphism and parental roles in the thorn-tailed rayadito (Furnariidae)” in The Condor 109(2):312-320 (2007)
  14. ^ Based on the formula of egg mass = 0.258m0.73, where m is body mass. From Rahn, H., Sotherland, P. and Paganelli, C. V., 1985. “Interrelationships between egg mass and adult body mass and metabolism among passerine birds” in Journal für Ornithologie 126:263-271.
  • Jaramillo, Alvaro; Burke, Peter & Beadle, David (2003) Field Guide to the Birds of Chile. Christopher Helm, London.