Parus

Eck, Siegfried, 2006, The Palaearctic Titmouse Species (Aves: Paridae: Parus sensu lato) — A current survey *, Zootaxa 1325, pp. 7-54 : 42

1. Parus [c.] dichrous

P. dichrous kangrae (WHISTLER, 1932) [Kangra, N Punjab]; P. d. dichrous BLYTH, 1844 [loc. typ. restr. according to BISWAS northern C Nepal]; P. dichrous izzardi BISWAS, 1955 [Thammu, Bhote Kosi­Tal, E Nepal, see Martens & Eck, 1995: 321–322, also under P 43]; P. dichrous wellsi BAKER, 1917 [greater Yangtse arc, NW Yunnan]; P. dichrous dichroides (PRZEWALSKI, 1876) [Gansu].

The population group: P 43 kangrae, dichrous , izzardi, dichroides, wellsi; Himalayas to W China. — Fig. Quinn: Plate 20: 69, in part.

* Vaurie (1957: 17–18; 1959: 489–490) described the coloration differences in 1959 as significant. see his publication. However, he did not even mention izzardi in 1957, and in 1979 placed it without commentary among the synonyms of dichrous . Martens and Eck (1995), in contrast, pointed out a distinct difference in wing length and relative tail length between dichrous s.str. and izzardi, and that should be repeated here. Although there is not much material ( dichrous 4 ♂♂, 2 ΨΨ, izzardi 9 ♂♂, 4 ΨΨ), the difference is striking. — Wing length of ♂♂: dichrous 65.5–69 mm (x = 67.1 mm), izzardi 71–75 mm (x = 72.4 mm). — TWI of ♂♂: dichrous 63.8–66.4% (x = 65.4 mm), izzardi 66.7–72.2% (x = 68.8 mm ± 1.68).