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A new species of the continental shelf hyperbenthic genus Pilarella is described, the first from the Indo-Pacific. This is the second species of Pilarella known, and the first description of a male in the genus. The new species is easily distinguished from other species of Pilarella (P. longicornis) based on: (1) short caudal rami, approximately 1.5 times longer than wide; (2) 2 setae on the mandibular endopod; (3) 6 setae on the maxillular coxal epipodite; and (4) in the female, a short left antennule reaching the posterior border of the genital double-somite. The new diagnosis of Pilarella differs from Metacalanus in the separation of ancestral segments IX–XII and XIV–XV of the antennule, and the presence of 5–6 setae on the maxillular praecoxal arthrite. Pilarella is also separated from Metacalanalis based on the absence of a seta on the third ancestral segment of the antennary exopod, the symmetry of legs 1–3, the presence of a medial basal seta on the female leg 5, and 2 lateral exopodal spines on the female leg 5. A molecular phylogenetic analysis of some representative genera of the family Arietellidae, including the present new species, recovers two arietellid clades (Metacalanus- and Arietellus-clades) as in previous studies. Dichotomous keys for the genera of Arietellidae and the species of Pilarella are included.

A new genus and species of calanoid copepods belonging to the group of Bradfordian families, Pogonura rugosagen. et sp. nov., is described from the deep-sea hyperbenthic layers off Nagannu Island, Okinawa Prefecture, southwestern Japan. Pogonuragen. nov. is similar to another Bradfordian genus Procenognatha in sharing the following characteristics: (1) segmentation of the antennule, fused segments II–IV, X–XI, XXVII–XXVIII in females and II–IV, X–XII, XXVII–XXVIII, right XXII–XXIII in males; (2) retained setae on the ancestral segments I–IV of the antennary exopod; (3) setules on the mandibular gnathobase; (4) 3 sclerotized setae on the maxillary endopod; (5) absence of sensory seta on the maxilliped; (6) large spinules on the posterior surface of the rami of legs 2 and 3; and (7) setation and segmentation of female leg 5. Pogonuragen. nov. is distinctly distinguished from Procenognatha by the following features: (1) reduction of a seta on the ancestral segment IX of the antennary exopod, (2) 8 setae (7 in Procenognatha) on the maxillular exopod, (3) 5 brush-like setae (6 in Procenognatha) on the maxillary endopod, and (4) reduction of right endopod of male leg 5. The systematic position of Pogonuragen. nov. in the Bradfordian families is also discussed. Although this new genus shares synapomorphies with some diaixid genera, an assignment of this genus to any Bradfordian family should be pending until the taxonomy of this family group is clearly settled.

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