Fig. 1

Geographic range of the eight taxa which make up the Z. dauma species complex with the subspecies identity of the Taiwan population uncertain. The precise border between aurea and toratugumi is uncertain. The range of dauma is shown as two populations: dauma W represents western populations from the Himalayas where the type specimen of dauma was derived; dauma E from approximately Sichuan and Yunnan eastwards was previously considered a distinct taxon socia (Thayer and Bangs 1912), though the name affinis has also been applied to populations (possibly overwintering migrants) from southern Thailand (Richmond 1902). The exact division between these two populations requires further study. The population on Taiwan island has variously been placed in affinis, horsfieldi, or toratugumi/aurea or have been recognized as an endemic taxon hancii. Black dots represent sampling locations for song vocalizations utilized in this study