Although the type material of N. sadurnii has never been figured and we have not examined it, there is no doubt that the name is a synonym of wolffi. In a letter of November 1975 Mr J. Bot informed us that his species is very close to Nassa wolffi Knudsen. He said he had seen material from Angola with all the characters of sadurnii. The same species was again described by Maldonado (1973) from specimens taken by shrimp trawlers. In the same paper, Ghisotti & Spada argued that the description of Nassa sadurnii Bot did not meet the requirements of 1CZN because it was not accompanied by an illustration. At the same time they provisionally named Maldonado's material Hinia frigens malacifanae n.ssp. "until further material can be studied for a definitive identification" In fact Bot's description is perfectly valid, while Ghisotti & Spada do not fulfil the requirements of ICZN §15 which states that "after I960, a new name proposed conditionally (...) is not available"

The upper bathyal of West Africa, from Namibia to Senegal at least; doubtful records further to the north. N. wolffi has been recorded a few times from the W Mediterranean, but all records are based on specimens with unreliable locality information, taken by fishing boats and said to come from the Alboran Sea and the fishing grounds off Catalonia. It is possible that the species occurs in the W Mediterranean, but the records need confirmation.