Bird dropping type caterpillar

Bird dropping type caterpillar

Observation - Bird dropping type caterpillar - Global. Description: Caterpillar resembling a bird dropping. Cant find anything like it in field guide. Only thing anything like it that I can find is a swallowtail which seems very unlikely. Any help appreciated

Caterpillar resembling a bird dropping. Cant find anything like it in field guide. Only thing anything like it that I can find is a swallowtail which seems very unlikely. Any help appreciated