Pseudomesochrinae Willen 1996

• Main Authors: Kim, Jong Guk, Lee, Jimin, Huys, Rony
• Format: Text
• Language: unknown
• Published: Zenodo 2021
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Hexanauplia; Harpacticoida; Miraciidae; Arctic; Arctic Ocean; Norway; Seta; Sedov; Bodin
• Online Access: https://dx.doi.org/10.5281/zenodo.5576303; https://zenodo.org/record/5576303

Key to species of Pseudomesochrinae Existing identification keys (Lang 1948; Coull 1973; Willen 1996; Wells 2007) are either out of date or unsound due to misinterpretations or observational errors (see footnotes in Table 2). A new key is presented below which, in the absence of male information for most species, is inevitably based on female characters only. Single male specimens have so far been reported on only four occasions: Pseudomesochra gemina (Coull 1973; Willen 1996), P. perplexa (Bodin 1968), and Keraia tamara (Smirnov, 1946) (Smirnov 1946). 1. Antennule ♀ with conspicuous projection on posterior distal corner of segment 1; antennary exopod enlarged, exp-2 with at least one very long element at its tip; P1 exp-1 elongate, longer than exp-2 and -3 combined; outer elements of P1 exp-1 and -2 setiform; P2–P4 exp-1 with inner seta......................................... Keraia Willen & Dittmar, 2009 …..2 - Antennule ♀ without conspicuous projection on posterior distal corner of segment 1; antennary exopod not enlarged, with apical setae of distal segment not excessively long; P1 exp-1 not elongate, shorter than exp-2 and -3 combined; outer elements of P1 exp-1 and -2 spiniform; P2–P4 exp-1 without inner seta....................... Pseudomesochra T. Scott, 1902 …..5 2. P2 enp-2 with one or two inner setae...................................................................... 3 - P2 enp-2 with three inner setae................................................. K. longirostrata Apostolov, 2011 3. Antennule ♀ 5-segmented; P3–P4 exp-3 with two inner setae.................................................. 4 - Antennule ♀ 6-segmented; P3–P4 exp-3 with three inner setae............................ K. tamara (Smirnov, 1946) 4 Cephalothorax about 1.3 times as long as maximum width; apical segment of antennary exopod with shorter seta about half the size of longest one; P5 endopodal lobe ♀ with one lateral and three apical setae................................................................................................ K. longiseta (Vasconcelos, George & Santos, 2008) - Cephalothorax about 1.1 times as long as maximum width; apical segment of antennary exopod with longest seta only slightly larger than shorter one; P5 endopodal lobe ♀ with all four setae arranged around apical margin................................................................................................ K. ricardae Willen & Dittmar, 2009 5 P2–P4 endopods 2-segmented........................................................................... 6 - P2–P4 endopods 3-segmented........................................................................... 8 6 P4 enp-2 with one inner seta; inner margin of caudal ramus with spinular patch near base........... P. affinis (Sars, 1920) * - P4 enp-2 with two inner setae; inner margin of caudal ramus without spinular patch near base......................... 7 7 P2 exp-3 with inner seta; caudal ramus slightly expanded proximally and with concave outer margin; P5 endopodal lobe ♀ with three very long setae............................................................. P. longifurcata T. Scott, 1902 - P2 exp-3 without inner seta; caudal ramus not expanded at base and with straight inner and outer margins; P5 endopodal lobe ♀ with long middle seta flanked by two shorter ones, all of which markedly shorter than in preceding species............................................................................................ P. divaricata (Sars, 1906) 8 P1 exp-2 with inner seta................................................................................ 9 - P1 exp-2 without inner seta............................................................................ 16 9 Antennule ♀ 5-segmented; P1 enp-1 with inner seta.......................................... P. media (Sars, 1911) - Antennule ♀ 6- or 7-segmented; P1 enp-1 without inner seta.................................................. 10 10 P2–P4 exp-3 with one inner seta; P2–P3 enp-3 with one inner seta; P4 enp-3 with three elements.... P. latifurca (Sars, 1911) - P2–P4 exp-3 with two, three, three setae, respectively; P2–P3 enp-3 with two inner setae; P4 enp-3 with four elements.... 11 11 Antennule ♀ 6-segmented; P2–P4 exp-3 with two outer spines................................................ 12 : Published as part of Kim, Jong Guk, Lee, Jimin & Huys, Rony, 2021, New records of Pseudotachidiidae from South Korea, including a key to species of the Pseudomesochrinae (Copepoda: Harpacticoida), pp. 387-422 in Zootaxa 5051 (1) on page 412, DOI: 10.11646/zootaxa.5051.1.16, http://zenodo.org/record/5563793 : {"references": ["Lang, K. (1948) Monographie der Harpacticiden. Vols. 1 & 2. Hakan Ohlsson, Lund, 1682 pp.", "Coull, B. C. (1973) Meiobenthic Harpacticoida (Crustacea, Copepoda) from the deep sea off North Carolina III. The families Tisbidae Stebbing emend. Lang, Thalestridae Sars emend. Lang, and Diosaccidae Sars. Transactions of the American microscopical Society, 92, 592 - 603. https: // doi. org / 10.2307 / 3225270", "Willen, E. (1996) Pseudomesochra T. Scott, 1902 as a member of the Paranannopidae Por 1986 (Copepoda, Harpacticoida) with a description of three new species. Senckenbergiana maritima, 28, 81 - 109. https: // doi. org / 10.1007 / BF 03042824", "Wells, J. B. J. (2007) An annotated checklist and keys to the species of Copepoda Harpacticoida (Crustacea). Zootaxa, 1568 (1), 1 - 872. https: // doi. org / 10.11646 / zootaxa. 1568.1.1", "Bodin, P. (1968) Copepodes Harpacticoides des etages bathyal et abyssal du golfe de Gascogne. Memoires du Museum national d'Histoire naturelle, Paris, Nouvelle Serie (A), 55 (1), 1 - 107.", "Smirnov, S. S. (1946) Novye vidy Copepoda Harpacticoida iz severnogo ledovitogo okeana. [New species of Copepoda-Harpacticoida from the northern Arctic Ocean]. Trudy Dreifuyuschei Ekspeditsii Glavsevmorputi na Ledokol'nom Parokhode ' G. Sedov', 1937 - 1940 gg, 3, 231 - 263. [in Russian with English summary]", "Willen, E. & Dittmar, J. (2009) A new genus of Pseudomesochrinae Willen, 1996 (Copepoda, Harpacticoida, Pseudotachidiidae) from the Guinea Basin. Zootaxa, 2096 (1), 287 - 298. https: // doi. org / 10.11646 / zootaxa. 2096.1.16", "Scott, T. (1902) Notes on gatherings of Crustacea collected by the fishery steamer \" Garland \", and the steam trawlers \" Star of Peace \" and \" Star of Hope \", of Aberdeen, during the year 1901. Reports of the Fishery Board for Scotland, Edinburgh, 20 (3), 447 - 485, pls. XXII - XXV.", "Apostolov, A. (2011) BIOICE programme. Les Harpacticoides marins (Crustacea, Copepoda) d'Islande. Libra Scorp, Bourgas, 368 pp.", "Vasconcelos, D. M., George, K. H. & Santos, P. J. P. (2008) First record of the genus Pseudomesochra T. Scott (Harpacticoida: Pseudotachidiidae) in the South Atlantic with description of a deep-sea species: Pseudomesochra longiseta sp. nov. In: Martinez Arbizu, P. & Brix, S. (Eds.), Bringing Light into Deep-sea Biodiversity. Zootaxa, 1866 (1), 337 - 348. https: // doi. org / 10.11646 / zootaxa. 1866.1.17", "Sars, G. O. (1920) Copepoda Supplement. Parts V & VI. Harpacticoida (continued). An Account of the Crustacea of Norway, with Short Descriptions and Figures of all the Species, 7, 53 - 72, pls. XXXIII - XLVIII.", "Sars, G. O. (1906) Copepoda Harpacticoida. Parts XV & XVI. Diosaccidae (concluded), Canthocamptidae (part). An Account of the Crustacea of Norway, with Short Descriptions and Figures of all the Species, 5, 173 - 196, pls. CXIII - CXXVIII.", "Sars, G. O. (1911) Copepoda Harpacticoida. Parts XXXI & XXXII. Supplement (continued). An Account of the Crustacea of Norway, with Short Descriptions and Figures of all the Species, 5, 369 - 396, supplement pls. 11 - 26."]}