During recent cruises of R.R.S. ‘Discovery’ in the eastern North Atlantic an investigation has been made of the depth distribution and diurnal migration of the pelagic fauna in selected oceanic areas. This continuing programme has entailed intensive mid-water sampling with opening-closing nets, fishing discrete depth horizons mainly within the upper 1000 m but also on occasion at greater depths. Hauls made during the cruise of January-April 1968 in a position 11°N, 20°W, south-east of the Cape Verde Islands, yielded 43 specimens of an apparently new species of the genus Acanthephyra. A further 113 specimens were taken during a subsequent cruise to the same area and the species has also been recorded in a sample collected in the Indian Ocean during the International Indian Ocean Expedition.

Having examined the literature and concluded that the species was undescribed the author referred to the large collection of decapod Crustacea that had been amassed as a result of cruises of ships of the Discovery Committee made prior to 1939. This material, together with that taken on the Dana Expeditions, had formed the subject of Dr Stanley W. Kemp's extensive studies on the Oplophoridae (Kemp, 1939), consequently the carefully preserved, labelled, and identified specimens represent a unique reference collection. It proved to contain five specimens identical to those taken at 11°N in 1968. Not unexpectedly Kemp had realized their uniqueness and had not only designated the type but named it. A description, however, was never published although it was prepared and has in part survived.