African stonechat

The African stonechat or common stonechat (''Saxicola torquatus'') is a species of the Old World flycatcher family (Muscicapidae), inhabiting sub-Saharan Africa and adjacent regions. Like the other chats, it was long assigned to the thrush family (Turdidae), to which the chats are convergent. Its scientific name refer to its appearance and habitat and means "collared rock-dweller": ''Saxicola'' from Latin ''saxum'' ("rock") + ''incola'' ("one who dwells in a place"), ''torquatus'', Latin for "collared".

In the past ''S. torquatus'' usually referred to the entire "common stonechat" superspecies and some sources still keep it that way, but all available evidence strongly supports full species status for the European (''S. rubicola'') and the Siberian stonechat (''S. maurus'') of temperate Eurasia, in addition to the island-endemics Fuerteventura chat (''S. dacotiae'') and Réunion stonechat (''S. tectes'') which were never unequivocally accepted into ''S. torquatus''. The Madagascar stonechat is also considered distinct. In addition, the well-marked populations of the Horn of Africa uplands may well qualify for an additional species.Wittmann et al. (1995), Urquhart & Bowley (2002)

Systematics and taxonomy

In 1760, the French zoologist Mathurin Jacques Brisson included a description of the African Stonechat in his ''Ornithologie'' based on a specimen collected from the Cape of Good Hope in South Africa. He used the French name ''Le gobe-mouche à collier du Cap de Bonne Espérance'' and the Latin ''Muscicapa Torquata Capitis Bonae Spei''. The two stars (**) at the start of the section indicates that Brisson based his description on the examination of a specimen. Although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature. When in 1766 the Swedish naturalist Carl Linnaeus updated his ''Systema Naturae'' for the twelfth edition, he added 240 species that had been previously described by Brisson. One of these was the African Stonechat. Linnaeus included a brief description, coined the binomial name ''Muscicapa torquata'' and cited Brisson's work. The specific name is from Latin ''torquatus'' "collared". This species is now placed in the genus ''Saxicola'' that was introduced by the German naturalist Johann Matthäus Bechstein in 1802.

The closest relative of this species are apparently not the Eurasian populations but the Réunion stonechat (''S. tectes''), but still the "white-collared" ''Saxicola'' form a distinct group in the genus. ''S. torquatus'' and ''S. tectes'' form a sub-Saharan African lineage that diverged from the Eurasian one in the Late Pliocene, roughly 2.5 million years ago. Réunion was colonized shortly thereafter, indicating a rapid expansion along the Indian Ocean coast of Africa. With the Sahara drying out in the subsequent Quaternary glaciation, the African and Eurasian populations became isolated for good.

The recent separation as species was proposed after mtDNA cytochrome ''b'' sequence and nDNA microsatellite fingerprinting analysis of specimens of the subspecies ''Saxicola torquatus axillaris'' but not ''S. t. torquatus'', and hence this species was briefly known as ''S. axillaris''.

Subspecies

There are 13 recognised subspecies. They differ slightly in size, and more in the extent of the orange-red on the upper breast of the males, and whether the lower breast is white with a distinct boundary from the upper breast, or pale orange with an indistinct boundary from the darker upper breast. The extent of the orange-red also varies with time of year, often extending on to the belly outside the breeding season.
* ''S. t. felix'' Bates, 1936 – southwest Saudi Arabia and west Yemen
* ''S. t. albofasciatus'' Rüppell, 1840 – southeast Sudan and northeast Uganda to central Ethiopia
::upper breast black, not orange-red
* ''S. t. jebelmarrae'' Lynes, 1920 – east Chad and west Sudan
* ''S. t. moptanus'' Bates, 1932 – Senegal and south Mali
:The smallest subspecies.
* ''S. t. nebularum'' Bates, 1930 – Tropical West Africa from Sierra Leone to west Ivory Coast
:Extensive orange-red on breast and also flanks.
* ''S. t. axillaris'' ( Shelley, 1885) – east Democratic Republic of the Congo, Kenya, north and west Tanzania
* ''S. t. promiscuus'' Hartert, 1922 – south Tanzania to east Zimbabwe and west Mozambique
:Very limited orange-red on uppermost part of breast only.
* ''S. t. salax'' ( Verreaux, J & Verreaux, E, 1851) – east Nigeria to northwest Angola, Bioko Island
* ''S. t. stonei'' Bowen, 1931 – east and south Angola to southwest Tanzania south to north South Africa and Botswana
* ''S. t. clanceyi'' Courtenay-Latimer, 1961 – coastal west South Africa
* ''S. t. torquatus'' (Linnaeus, 1766) – central South Africa
* ''S. t. oreobates'' Clancey, 1956 – Lesotho
* ''S. t. voeltzkowi'' Grote, 1926 – Grande Comore

Description

The males have a black head, a white half-collar, a black back, a white rump, and a black tail; the wings are black with a large white patch on the top side of the inner wing. The upper breast is usually dark orange-red, with a sharp or gradual transition to white or pale orange on the lower breast and belly depending on subspecies. In a few, black replaces the orange breast feathers in part or entirely.Urquhart & Bowley (2002)

Females have brown rather than black above and on the head with an indistinct paler eyebrow line, chestnut-buff rather than orange below, and less white on the wings. Both sexes' plumage is somewhat duller and streakier outside the breeding season.

Distribution and habitat

It has a scattered distribution across much of sub-Saharan Africa, occurring locally as far north as Senegal and Ethiopia. Outlying populations are found the mountains of southwest Arabia and on Madagascar and Grande Comore. It is non-migratory, moving only locally if at all. As a result, it has developed much regional variation, being divided into 13 subspecies.

References

Sources

* Boulton, Rudyerd & Rand, A.L. (1952). A collection of birds from Mount Cameroon. '' Fieldiana Zool.'' 34(5):35-64
Fulltext
at the Internet Archive
*
* Urquhart, Ewan & Bowley, Adam (2002). ''Stonechats. A Guide to the Genus Saxicola''. Christopher Helm, London.
* Wittmann, U.; Heidrich, P.; Wink, M. & Gwinner, E. (1995). Speciation in the Stonechat (''Saxicola torquata'') inferred from nucleotide sequences of the cytochrome b-gene. ''Journal of Zoological Systematics and Evolutionary Research'' 33(2):116-122. HTML abstract

External links

*African stonechat
Species text in The Atlas of Southern African Birds

{{Taxonbar, from=Q1315689

African stonechat
African stonechat
African stonechat
African stonechat
African stonechat
Taxa named by Carl Linnaeus