Italiensperling bald als eigene Art geführt?
Das Taxonomic Sub-Committee des BOU Records Committees empfiehlt die Anerkennung des Italiensperlings als eigene Art:
Taxonomic recommendations for Western Palearctic birds: 10th report. IBIS 157 (2015): 193-200. (George Sangster, J. Martin Collinson, Pierre-André Crochet, Guy M. Kirwan, Alan G. Knox, David T. Parkin and Stephen C. Votier)
House Sparrow Passer domesticus
The taxonomic status and evolutionary origin of the Italian Sparrow have a long and convoluted history (reviewed by Töpfer 2006). Morphologically, italiae has a unique combination of characters compared with domesticus and hispaniolensis but is distinct from both in most of its range (Johnston 1969). Three molecular studies, one based on mitochondrial DNA and microsatellites and the others on nuclear DNA sequences, provide compelling evidence for a hybrid origin of italiae (Elgvin et al. 2011, Hermansen et al. 2011, 2014).
There is a narrow hybrid zone between domesticus and italiae in the southern Alps characterized by steep clines in species-specific male plumage traits (Lockley 1992, Hermansen et al. 2011). Morphological and molecular data show that italiae and domesticus are probably both diagnosably distinct and reproductively isolated (Lockley 1992, Hermansen et al. 2011, Trier et al. 2014).
In southern Italy, the morphological transition between italiae and hispaniolensis is less clear-cut because Italian Sparrows on the Calabria Peninsula and Sicily approach Spanish Sparrows in some characteristics (larger bibs than those further north, and partially black-streaked flanks; reviewed by Töpfer 2006). However, assignment tests based on microsatellite data show that assignment probability intervals of Italian Sparrows on the Calabria Peninsula and Sicily do not overlap with those of ‘pure’ Spanish Sparrow from Sardinia (Hermansen et al. 2011). Importantly, on the Gargano Peninsula in southeast Italy italiae breeds sympatrically with hispaniolensis and morphological or molecular data show no indications of interbreeding (Hermansen et al. 2011, Trier et al. 2014).
Italian Sparrow is currently (Cramp & Perrins 1994) not recognized at any taxonomic level but it seems clear that it is a valid taxon: it has a unique combination of morphological characters, it is geographically restricted (i.e. a population) and it shows evidence of reproductive isolation from both parental species. Treatment as a subspecies of P. domesticus (Beaman 1994, Jiguet 2003) or as a subspecies of P. hispaniolensis (Clement et al. 1993, Eck 1996, Baumgart 2003, Töpfer 2006) implies that italiae is more closely related to these species than to the other species, which is difficult to maintain if P. italiae is of hybrid origin. Species rank of italiae is appropriate given (1) its distinctive morphology, (2) strong evidence for its hybrid origin and (3) evidence for a substantial degree of reproductive isolation from both P. domesticus and P. hispaniolensis. Species rank was previously proposed by Massa (1989), Fulgione and Milone (1998) and Stephan (1999, 2004). Thus, Italian Sparrow is recognized as a full species and listed between House and Spanish Sparrows.
Populations in the Middle East, Central Asia and India have been separated as Indian Sparrow based on differences in morphology and sympatric breeding with limited interbreeding in some areas of contact (Gavrilov 1965) but many details remain unclear. Populations of the domesticus group and indicus group (sensu Cramp & Perrins 1994) show no differentiation in mitochondrial DNA (Sætre et al. 2012). Based on current evidence, Indian Sparrow is best considered conspecific with House Sparrow.
House Sparrow Passer domesticus (polytypic)
Italian Sparrow Passer italiae (monotypic)
Spanish Sparrow Passer hispaniolensis (polytypic)