Three new genera of misophrioid copepods from the near-bottom plankton community in the North Atlantic Ocean G. A. Boxshall Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD Introduction Only three species of the copepod order Misophrioida have been described, Misophria pallida Boeck 1864, Benthomisophria palliata Sars 1909 and B. cornuta Hulsemann & Grice 1964. Despite the small number of species the misophrioids have attracted interest because of the combination of characters that they exhibit, drawn from both the gymnoplean and podoplean lineages within the Copepoda. Attention has recently been drawn to the unique characters that misophrioids display; the possession of a carapace-like posterior extension of the cephalosome, the lack of a nauplius eye in a free living copepod, the distensibility of the gut and the retention of the antennary glands as the functional excretory organs of the adult (Boxshall, 1982). These characters, together with the abbreviated lecithotrophic nauplius phase of the life cycle, can be interpreted collectively as evidence of a bathypelagic origin of the Misophrioida. This interpretation is supported by the discovery of several new misophrioid taxa from the deep North Atlantic Ocean, which was reported at the First International Conference on Copepoda held at Amsterdam in August 1981 (Boxshall, in press). A total of 37 misophrioids was taken in a single haul fished near the bottom in 3000 m of water to the south west of the Azores. Fourteen of these were B. cornuta, 8 were B. palliata and 15 represented previously undescribed taxa. Three new genera and species are here described on the basis of 13 of these specimens, the remaining 2 specimens being too badly damaged for description. The new genera are of great phylogenetic significance as they exhibit some very plesiomorphic characters which provide fresh insights on the nature of the appendages of the common ancestor of the Copepoda as a whole. The new records of B. cornuta and B. palliata further extend their known geographical ranges. Family MISOPHRIIDAE Genus ARCHIMISOPHRIA nov. DIAGNOSIS. As for type species. TYPE SPECIES. Archimisophria discoveryi gen. et sp. nov. Archimisophria discoveryi gen. et sp. nov. Adult female (Fig. 1A) body length 1-1 to 14 mm. Prosome large, apparently 4-segmented but with first free thoracic somite entirely concealed beneath a carapace-like extension from the posterior margin of the maxilliped-bearing somite. Nauplius eye absent. Prominent anteriorly-directed rostrum visible from dorsal aspect, not fused to labrum (Fig. 1 B). Cone organs not observed but large mass of glandular tissue present on sides of cephalosome beneath usual location of cone organs. Urosome 6-segmented (Fig. 1C). Surface Bull. Br. Mus. nat. Hist. (Zool.) 44(2): 103-124 Issued 24 February 1983
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