Poecile

Subgenus Poecile, type species Parus palustris L., 1758

(Marsh Tits, Willow Tits, chickadees and allies)

The Marsh Tits (P. palustris) can be extensively subdivided, in the western as well as the eastern Palaearctic. The Siberian brevirostris group (high bill, small feet, long tail) is clearly distinct from the allopatric palustris (although cyt­ b distance only 0.6 %, see GILL et al., 2005: 127) and the Chinese (parapatric?) hellmayri group. Parus hypermelaenus is here tentatively regarded as a species.

Field work in Talish induced Loskot (1977, 1978, 1987) to ascribe species status to Parus lugubris hyrcanus: he observed that its voice deviates from that of other Sombre Tits, and it chisels out its nest holes itself, which would place it closer to the Willow Tits! Stepanjan (1978, 1990) and Harrap and Quinn (1996) shared this view of species independence. Löhrl (1982: 127) demonstrated experimentally that Balkan Sombre Tits (P. lugubris lugubris) also chop up rotten wood in a cavity and carry it out, but probably because of their body size do not prepare their own nest holes; hyrcanus is distinctly smaller.

Eck (1980 and earlier) had proposed subdividing the Willow Tits to a greater extent on one hand, while on the other hand considering them closely related to the American chickadees as was formerly customary. Thönen and Fujimaki (1995: 174) and Thönen (1996) point out that Parus atricapillus turneri in Alaska sings “alpine”, like birds of the European montanus group and unlike the remaining Black­capped Chickadees, with which it appears to hybridise (Thönen 1996: 24). Thönen (l.c.) also emphatically declares that it would be erroneous to separate songarus in the Tian Shan from the Willow Tit at species level. Martens and Nazarenko (1993) as well as Martens et al. (1995) analysed the songs of Palaearctic Willow Tits regarding their historic differentiation; cf. also Kvist et al. (2001). The distribution was most recently presented by Quaisser and Eck (2002/03). It exhibits several obviously parapatric situations (l.c., maps 3, 4!): in Europe between very similar representatives with different song forms, namely the salicarius, montanus and borealis complexes; in Asia between very dissimilar representatives with different but also consistent song forms, namely baicalensis­songarus, weigoldicus­affinis, baicalensisanadyrensis. Parus weigoldicus is evidently parapatric with P. m. affinis, is also separated by a considerable cyt­ b distance, and is here tentatively, and in analogy to P. hypermelaenus and P. teneriffae, considered an (allo)species.