Russet Sparrow - Taxonomy

Taxonomy

The Russet Sparrow was first scientifically described, as Fringilla rutilans, by the Dutch zoologist Coenraad Jacob Temminck in 1835, from a specimen collected in Japan. Its specific name comes from the Latin rutilus, "of a glowing or auburn red". It has usually been placed in the genus Passer, and within this genus it is seen as a part of the "Palearctic black-bibbed sparrow" group, which includes the Eurasian Tree Sparrow as well as the House Sparrow. It has generally been seen as a close relation of the House Sparrow, and Richard Meinertzhagen even considered it to be the same species as the Somali Sparrow, one of the House Sparrow's closest relatives. However, studies of mitochondrial DNA indicate that the Russet Sparrow is an early offshoot or basal species among the Palearctic black-bibbed sparrows. While mitochrondrial DNA suggest speciation in Passer occurred during the Miocene and Pliocene, British ornithologist J. Denis Summers-Smith considers the Russet Sparrow to have separated from the other Palearctic black-bibbed sparrows about 25,000 to 15,000 years ago, during the last glacial period. During this time, sparrows would have only been found in isolated ice-free refugia, such as the lower Yangtze valley, which Summers-Smith considers the most likely centre of evolution for the Russet Sparrow.

Thirteen subspecies have been described, but only three are widely recognised, these differing largely in the colour of their underparts. The nominate subspecies Passer rutilans rutilans breeds in Japan, Korea, Taiwan, and southeastern and central China. The subspecies intensior, described in 1922 by Walter Rothschild from Yunnan, breeds in southwest China and parts of India, Burma, Laos, and Vietnam. In a large part of Sichuan intensior intergrades with the nominate subspecies, and a number of subspecies names have been proposed for the intergrades. The subspecies cinnamomeus, described in 1836 by John Gould from the northwestern Himalayas, breeds from northern Arunachal Pradesh to Nuristan in Afghanistan.