Morphological characters of the tongue skeleton reveal phylogenetic relationships within the Corvidae (Oscines, Passeriformes)

I thank Gerald Mayr (Forschungsinstitut Senckenberg, Frankfurt am Main, Germany) and Jo Cooper (Natural History Museum, Tring, Great Britain) for providing access to the skeleton collections. I also thank Mark Peck (Royal Ontario Museum, Canada), Mark Blair Robbins (University of Kansas/Museum of Natural History, Lawrence, USA), Paul Sweet and David Willard (Field Museum of Natural History, Chicago, USA) for loans of additional specimens. I also thank Andrzej Elzanowski (University of Wroclaw, Poland) for calling my attention to certain literature, as well as Camilla Myers, John R. Stewart and an anonymous referee for their helpful comments. I am very grateful to J. Tyler Faith and Amy L. Rector for proof-reading the manuscript. This study was supported by a German Research Foundation (DFG) grant (MA 2328/3–2) and by a Leopoldina Research Fellowship (BMBF-LPD 9901/8–183).

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1. Paraglossalia: (0) rostral tips pointed, symphysis paraglossalis rostralis extended, (1) rostral tips blunt and truncated, symphysis paraglossalis rostralis short (Fig. 2a, g ).

2. Paraglossalia, proc. articulares paraglossales: (0) meet medially, (1) do not meet medially, more or less triangular in outline and reduced in size (Fig. 2a, g ).

3. Paraglossalia, ventral surface: (0) smooth, (1) equipped with cone-shaped proc. paraglossalis ventralis (Fig. 2c, i ).

4. Paraglossalia, dorso-ventrally concave: (0) no, (1) yes (Fig. 3f, g ).

5. Basihyale, rostro-ventral margin of facies articularis paraglosso-basihyalis: (0) pointed, projects farther rostrally than its rostro-dorsal margin, (1) truncated, (2) greatly reduced (Figs 2b, h, 3d, g ).

6. Basihyale, rostral end distinctly broadened: (0) no, (1) yes (Fig. 3e, f ).

7. Basihyale, elongated and with sagittal crest: (0) no, (1) yes (Fig. 3d, g ).

8. Urohyale: (0) ossified, spoon-shaped and dorso-ventrally flattened, (1) unossified, cartilaginous (Fig. 2a, g ) (Giebel 1858; James et al. 2003).

9. Quadrate with additional condyle articulating with rostral cotyla of the lower jaw (buttress complex): (0) absent, (1) present (Zusi 1987).