There is an unique lectin named “SeviL” which has binding affinity to ganglioside GM1band and its precursor form, asialo-GM1.
https://www.nature.com/articles/s41598-020-78926-7
This lectin could be extracted from Septifer virgatus.
A picture below shows its cluster.
The amount of Sevil contained in one Septifer virgatus is about 0.004mg. Taking the popuration around there into consideration, there would be 100g SeviL per 10 square meters.
That day was cloudy and windy, but here is a shore where Septifer virgus is living.