| Abstract: | The tanaidacean tribe Agathotanaini, which was formerly the family Agathotanaidae, is well-represented in the Rockall Trough and Bay of Biscay areas of the North-east Atlantic. Five species have been recorded from depths of 1160–4829 m. Agathotanais ingolfi is the most numerous and one of the most widely distributed tanaidacean species in the region, and is often predominant in epibenthic sled samples from 1500–2500 m. Less numerous and frequent are three new species of Paragathotanais: P. nanus, P. robustus and P. gracilis. The first two are bathyal in distribution, and the last is abyssal. A new monospecific genus is established for Metagathotanais insulcatus, which has been recorded from the deepest part of the study region (4600–4800 m). Males of this tribe are characterized by their rigid pleopods bearing short terminal setae, and are otherwise very similar to the females. A key is provided for the identification of agathotanaids from the North-east Atlantic, including Agathotanais hanseni, and the genera Allodaposia and Paranarthrura, which should also be classified in the Agathotanaini. |
