所以真的没人知道吗

我看它俩嘴型略有不同，腿颜色也不一样我直接找不同

Black-and-yellow Grosbeak Mycerobas icterioides 黄腹拟蜡嘴雀
Male is very similar to male Collared. Black of phJnage is duller (less glossy), and has black thighs. Nape, upperparts and underparts are generally a purer, paler lemon-yellow.
——Birds of the Indian Subcontinent (Richard Grimmett, Carol Inskipp, and Tom Inskipp 2014)
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Black-and-yellow Grosbeak Mycerobas icterioides 黄腹拟蜡嘴雀
Adult males are extremely similar to male Collared Grosbeak, but black of plumage is duller (not glossy) and thighs are conspicuously black (not yellow); has a less pronounced orange 'collar' across upper mantle, and yellow in plumage is also paler than on male Collared.
Collared Grosbeak Mycerobas affinis 黄颈拟蜡嘴雀
Adult male breeding: very similar to adult male Black-and-yellow Grosbeak, but with nape to rump tinged golden-brown; thighs yellow, bill greyish-green.
Voices of the two species are distinctly different.
——Finches and Sparrows (Peter Clement 1993)