Proposal of two new genera of the family Zosimeidae Seifried (Copepoda: Harpacticoida): Heterozosime gen. nov. and Acritozosime gen. nov.

Keywords: deep sea, Korea, meiofauna, morphology, Pacific


In the Pacific Ocean, the taxonomy of the family Zosimeidae Seifried, 2003 is poorly understood and to date only five species of the genus Zosime Boeck, 1873 are known. During oceanographic cruises exploring the species diversity of harpacticoids, two undescribed zosimeid copepods were sampled from shallow Korean waters and the deep northwestern Pacific. A detailed morphological examination has led us to propose two new genera, Heterozosime gen. nov. for the Korean zosimeid H. tenuis gen. et sp. nov. and Acritozosime gen. nov. for the deep-sea zosimeid A. spinesco gen. et sp. nov. Both new genera exhibit a distinctive feature in that the first thoracic leg has a two-segmented exopod, in contrast to the three-segmented exopod of this leg in all known zosimeid genera. Furthermore, Acritozosime gen. nov. can also be discriminated from other genera by the two-segmented endopod in second to fourth thoracic legs and the reduced setal armatures of the second exopodal segment of antenna, the first endopodal segment of first to third thoracic legs and the third exopodal segment in second to fourth thoracic legs. A comparison of the fundamental structures of appendages suggests that A. spinesco gen. et sp. nov. experienced a unique evolutionary history within the Zosimeidae.


Bröhldick K.S.T. 2005. A new taxon of Idyanthidae (Copepoda, Harpacticoida) from the deep sea of the Angola Basin. Organisms Diversity & Evolution 5 (suppl. 1): 43–57.

Burgess R. 2001. An improved protocol for separating meiofauna from sediments using colloidal silica sols. Marine Ecology Progress Series 214: 161–165.

Easton E.E. & Thistle D. 2016. Do some deep-sea, sediment-dwelling species of harpacticoid copepods have 1000-km-scale range sizes? Molecular Ecology 25 (17): 4301–4318.

Fiers F. 1991. Three new harpacticoid copepods from the Santa Maria Basin off the Californian Pacific coast (Copepoda, Harpacticoida). Beaufortia 42 (2): 13–47. Available from [accessed 18 Jun. 2021].

Garlitska L.А., Chertoprud E.S., Portnova D.A. & Azovsky A.I. 2019. Benthic Harpacticoida of the Cara sea: species composition and bathymetric distribution. Okeanologiya 59 (4): 600–611. [In Russian].

George K.H. 2004. Meteorina magnifica gen. et sp. nov., a new Idyanthidae (Copepoda, Harpacticoida) from the plateau of the Great Meteor Seamount (Eastern North Atlantic). Meiofauna Marina 13: 95–112.

George K.H., Veit-Köhler G., Martínez Arbizu P., Seifried S., Rose A., Willen E., Bröhldick K., Corgosinho P.H., Drewes J., Menzel L., Moura G. & Schminke H.K. 2014. Community structure and species diversity of Harpacticoida (Crustacea: Copepoda) at two sites in the deep sea of the Angola Basin (Southeast Atlantic). Organisms Diversity & Evolution 14: 57–73.

George K.H., Pointner K. & Packmor J. 2018. The benthic Copepoda (Crustacea) of Anaximenes Seamount (eastern Mediterranean Sea) — Community structure and species distribution. Progress in Oceanography 165: 299–316.

Gheerardyn H., de Troch M., Vincx M. & Vanreusel A. 2009. Harpacticoida (Crustacea: Copepoda) associated with cold-water coral substrates in the Porcupine Seabight (NE Atlantic): species composition, diversity and reflections on the origin of the fauna. Scientia Marina 73 (4): 747–760.

Huys R. 1993. Styracothoracidae (Copepoda: Harpacticoida), a new family from the Philippine deep sea. Journal of Crustacean Biology 13 (4): 769–783.

Huys R. & Boxshall G.A. 1991. Copepod Evolution. The Ray Society, London.

Huys R., Gee J.M., Moore C.G. & Hamond R. 1996. Marine and Brackish Water Harpacticoid Copepods. Part 1. Synopses of the British Fauna (New Series) 51, Field Studies Council, Shrewsbury, UK.

Kim J.G. & Lee J. 2019. New records of benthic harpacticoids from Korea: I. Three new species of the genus Zosime Boeck (Copepoda: Harpacticoida: Zosimeidae). Marine Biology Research 15 (2): 210–239.

Kim J.G., Jung T.W. & Yoon S.M. 2016. A new species of Zosime (Copepoda: Harpacticoida: Zosimeidae) from shallow subtidal habitats in Korea, with notes on the genus. Zootaxa 4136 (2): 323–334.

Kitahashi T., Kawamura K., Kojima S. & Shimanaga M. 2013. Assemblages gradually change from bathyal to hadal depth: a case study on harpacticoid copepods around the Kuril Trench (north-west Pacific Ocean). Deep-Sea Research Part I: Oceanographic Research Papers 74: 39–47.

Kitahashi T., Kawamura K., Kojima S. & Shimanaga M. 2014. Bathymetric patterns of α and β diversity of harpacticoid copepods at the genus level around the Ryukyu Trench, and turnover diversity between trenches around Japan. Progress in Oceanography 123: 54–63.

Koller S. & George K.H. 2011. Description of a new species of Zosime Boeck, 1872 (Copepoda: Harpacticoida: Zosimeidae) from the Great Meteor Seamount, representing one of the few eurybathic Harpacticoida among the distinct plateau and deep-sea assemblages. Meiofauna Marina 19: 109–126.

Moura G. & Martínez Arbizu P. 2003. The phylogenetic position of the bathyal harpacticoids Aspinothorax gen. n. and Styracothorax Huys (Crustacea: Copepoda). Bulletin de l’Institut royal des Sciences naturelles de Belgique Biologie 73: 167–181.

Pointner K. 2017. Description of two new species of Zosime (Copepoda: Harpacticoida: Zosimeidae), including remarks on its phylogeny and distribution on the Great Meteor Seamount plateau (North-east Atlantic Ocean). Journal of Natural History 51 (37–38): 2283–2330.

Schmidt C., Lins L. & Brandt A. 2018. Harpacticoida (Crustacea, Copepoda) across a longitudinal transect of the Vema Fracture Zone and along a depth gradient in the Puerto Rico trench. Deep-Sea Research Part II: Topical Studies in Oceanography 148: 236–250.

Schmidt C., Sattarova V.V., Katrynski L. & Martínez Arbizu P. 2019. New insights from the deep: meiofauna in the Kuril-Kamchatka Trench and adjacent abyssal plain. Progress in Oceanography 173: 192–207.

Seifried S. 2003. Phylogeny of Harpacticoida (Copepoda): Revision of “Maxillipedasphalea” and Exanechentera. Cuvillier Verlag, Göttingen, Germany.

Seifried S. 2004. The importance of a phylogenetic system for the study of deep-sea harpacticoid diversity. Zoological Studies 43 (2): 435–445.

Shimanaga M., Kitazato H. & Shirayama Y. 2004. Temporal patterns in diversity and species composition of deep-sea benthic copepods in bathyal Sagami Bay, central Japan. Marine Biology 144: 1097–1110.

Shirayama Y., Kaku T. & Higgins R.P. 1993. Double-sided microscopic observation of meiofauna using an HS-slide. Benthos Research 44: 41–44.

How to Cite
Kim, J. G., & Lee, J. (2021). Proposal of two new genera of the family Zosimeidae Seifried (Copepoda: Harpacticoida): Heterozosime gen. nov. and Acritozosime gen. nov. European Journal of Taxonomy, 760(1), 32–60.
Research article