these species, either the saxaul sparrow formerly occurred in the deserts of Africa and Arabia, or each of the groups of Passer sparrows are of African origin. Across its Central Asian distribution, the saxaul sparrow occurs in six probably disjunct areas, and is divided into at least three subspecies. The nominate subspecies Passer ammodendri ammodendri inhabits three of these areas, one in the Syr Darya basin of Kazakhstan and Uzbekistan, and another to the south of Lake Balkhash and the north of Almaty, where it is only common in the valley of the Ili River. In a third area, sometimes recognised as a subspecies korejewi, ammodendri birds breed sporadically in parts of central Turkmenistan, Iran, and possibly Afghanistan, migrating to the south during the winter. The subspecies stoliczkae was named after Ferdinand Stoliczka in 1874 by Allan Octavian Hume, from specimens Stoliczka collected in Yarkand. This subspecies is separated from the other two subspecies by the Tian Shan mountains. It is found across a broad swath of China from Kashgar east to the far west of Inner Mongolia, through the areas around the Taklamakan Desert (but probably not in the inhospitable desert itself), and through the east of Xinjiang, northern Gansu, and the fringes of southern Mongolia. In the extreme west of the Gobi Desert a disjunct population separated from the other stoliczkae birds by the Gurvan Saikhan Uul mountains occurs, which is sometimes separated as a subspecies timidus. The subspecies nigricans, described by ornithologist L. S. Stepanyan in 1961, is found in northern Xinjiang's Manasi River valley. Habitat The saxaul sparrow is found in remote parts of Central Asia, where its distribution is believed to fall into six disjunct areas, although this is uncertain due to the scarcity of records. It is found in deserts, especially around rivers and oases. It is usually found around shrubs such as saxaul (Haloxylon), poplar (Populus), or tamarisk (Tamarix). Sometimes it occurs around settlements and grain fields, especially during the winter. It is not believed to be threatened, since it is reported as locally common across a wide range, and hence it is assessed as Least Concern on the IUCN Red List. However, it seems to have lost large parts of its range to the intensification of agriculture and desertification caused by overgrazing. Behaviour Little is known of the saxaul sparrow's behaviour, because of its remote range. It is shy in many areas,