The auction is for a worthy cause, the Locus Science Fiction Foundation. The illustration is from the collection of the late Locus publisher Charles N. Brown.
Mundy's adventure stories, many set in a mysterious and mystical India during the Raj, have influenced a number of fantasists: Leigh Brackett, Marion Zimmer Bradley, Robert E. Howard, Fritz Leiber, Andre Norton. S.M. Stirling's The Peshawar Lancers (2002) is a more recent homage.
Coll was just as influential among fantasy illustrators, for his pen-and-ink wizardry and his iconic visualizations of Arthur Conan Doyle's Professor Challenger and Sax Rohmer's Fu Manchu. Al Williamson is one obvious descendant. As collector Jim Vadeboncoeur puts it on his Coll appreciation page:
There were science fiction stories before The Lost World ... just as there were authors before Mundy and Rohmer who wrote horror and adventure stories. What there wasn't, before Coll, was the illustrative style and technique to match the literary ones. Coll invented that style, developed it, popularized it, and disseminated it to the coming generations of artists who saw it and knew that it was right.