43 minutes ago, Duvel said:
You are spot on @Thanks for the Crepes!
I just got the confirmation from a Cantonese friend that these are gills - Cantonese "Peng Yu Sai". Probably from manta ray (there is some sort of controversy on obtaining them)
Indeed there is. Stocks of manta rays have plummeted in recent years because of the demand from Chinese Traditional Medicine.
https://www.nytimes.com/2016/01/07/world/asia/china-manta-ray-conservation.html
But I was correct with my TCM connection!