I used Gephi to make a graph of all the keywords connected to bone skates in the WBRG reference database.
Most of the results aren’t very surprising. Of course bone skates are strongly linked to worked bone, bone, Europe, and the Middle Ages (1000–1500).
More surprising are the links to North America and to whales (Cetacea), found in references 1553 and 3705, which have to do with indigenous people in the Arctic. Molluscs and some of the other surprising keywords are connected via general works covering a range of objects, not just skates.
Some other interesting references linked to bone skates are numbers 1353 and 852.