New species of akalat

A new species of akalat Sheppardia has recently been described from Tanzania (Beresford, P, Fjeldså & Kiure, J 2004. A new species of akalat (Sheppardia) narrowly endemic in the Eastern Arc of Tanzania. Auk 121: 23-34). Akalats are small chat-like or robin-like birds, (most) closely related to the genera Saxicola, Erithacus, Cossypha, Alethe, Luscinia, Erythropygia and Oenanthe. The new species, Rubeho Akalat Sheppardia aurantiithorax (Dutch name: Rubehojanfrederik), was mistnetted (but not collected) already in 1989 in the Ukaguru mountains, c 150 km north of the range of Iringa Akalat S lowei, of which it was then assumed to represent an isolated population. In February 2000, Jacob Kiure collected a specimen in the Rubeho mountains and later more specimens in the Ukaguru mountains, and swiftly concluded that these birds were diagnosably distinct from Iringa Akalat, as well as from Usambara Akalat S montana, the other akalat restricted to high-altitude forest of the West Usamabara and Udzungwa mountains and adjacent highlands north of Lake Malawi. The three species share as unique character the presence of a bicoloured (orange and white) pre-ocular loral spot and reduced rictal bristles. Rubeho Akalat differs from its presumed sister taxa, Iringa and Usambara Akalat, by a deep orange throat and upperbreast, without white in the centre of the throat, and a richer copper wash on the upperparts. Molecular analysis supported the specific status of the new taxon. The vocal repertoire comprises a series of dry rattles, deeper in pitch than similar calls of Iringa Akalat and never followed by the ascending sharp whistles often heard in Iringa Akalat. The territorial song and other vocalizations during the breeding season have not yet been recorded.
The scientific name of Rebuho Akalat (aurantiithorax) refers to the ochraceous colour on the throat and upperbreast and the English name to the type locality and principal highland within its restricted range. It has been recorded in montane forest at 1800-2200 m above sea level in the Rubeho highland, in the small Wota forest in the Wota mountains and in the Ukaguru mountains and seems to be fairly common. Its range is separated from that of Iringa Akalat by the erosion gap of the Great Ruaha river. In general, the eastern African akalats have been thought to be sedentary with only minor seasonal movements. However, one specimen of the new species was mistnetted in a lowland forest at only 400 m above sea level, north-east of the Uluguru mountains and more than 100 km east of the known breeding range, where there is also a record of Iringa Akalat (in 1962). These records suggest some dispersal in the dry winter season; the possibility that these records may represent (extinct) local populations should, however, not be ruled out.
The discovery of this new endemic species of the Eastern Arc montane forests emphasizes the complex biodiversity of the region and underscores the need for effective conservation measures. The Eastern Arc region has provided some other taxonomic surprises, most notably the discovery of a new species of partridge placed in a separate monotypic genus, Undzungwa Partridge Xenoperdix udzungwensis, which was described in 1994. It was first noted when scientists noted a pair of strange feet in a cooking pot in a forest camp in the Undzungwa mountains in July 1991; subsequent investigations revealed the presence in the area of a species new to science.
ENNO B EBELS