Fig. 6 in Echinoderes landersi Grzelak & Sørensen 2022, sp. nov.

Fig. 6. Boundary in China between distribution areas of Cuculus optatus and Cuculus saturatus during breeding season. The dashed line is the boundary that Johnsgard (1997) used to separate Cuculus optatus and Cuculus saturatus. The solid line is the boundary suggested by this study. a: Northern mainland China, b: Taiwan Island. Geographic base map is from Google Maps (Google, USA).