Abstract
Samples collected during the Sergipe Continental Slope Environmental Characterization Project coordinated by PETROBRAS (The Brazilian Petroleum Company) revealed a new species of the family Pseudotachidiidae Lang, 1936 (Copepoda, Harpacticoida), Pseudomesochra longiseta sp. nov. This is the first record of the genus Pseudomesochra T. Scott, 1902 for the South Atlantic. Pseudomesochra longiseta sp. nov. can be distinguished from all species of the genus Pseudomesochra by the presence of four sensilla on the rostrum and a very long terminal “rat-tail” seta on the second segment of the antenna. It shares with P. tamara Smirnov, 1946 the addition of one inner seta on the first exopodal segment of the swimming legs 2–4 (P2–P4), a character absent in the remaining species of the genus. Pseudomesochra longiseta sp. nov. is the fourth species described within this genus with 2-segmented P2–P4 endopods. The inclusion of the new species in Pseudomesochra requires the modification of some autapomorphic characters of the genus, the most important being the presence of four sensilla on the rostrum, a character shared with other Pseudotachidiidae.
References
Becker, K.H. (1974) Eidonomie und Taxonomie abyssaler Harpacticoidea (Crustacea, Copepoda) Teil I. Cerviniidae-Ameiridae. „Meteor“ Forschungsreise-Ergebnisse D 18, 1–28.
Becker, K.H. & Schriever, G. (1979) Eidonomie und Taxonomie abyssaler Harpacticoidea (Crustacea, Copepoda) Teil III. 13 Neue Tiefsee-Copepoda Harpacticoidea der Familien Canuellidae, Cerviniidae, Tisbidae, Thalestridae, Diosaccidae und Ameiridae. „Meteor“ Forschungsreise-Ergebnisse D 31, 38–62.
Bodin, P. (1968) Copépodes Harpacticoïdes des étages bathyal et abyssal du Golfe de Gascogne. Mémoires du Muséum National d´Histoire Naturelle, A55 (1), 61–68.
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(4), 592–603.
Drzycimski, I. (1968) Neue Harpacticoida (Copepoda) aus dem westnorwegischen Küstengebiet. Sarsia, 31, 15–24.
Lang, K. (1948) Monographie der Harpacticiden. Stockholm A-B. Nordiska Bokhandeln, 1683pp.
Sars, G.O. (1911) Copepoda Harpacticoida. Parts XXIX & XXX. Tachidiidae (concluded), Metidae, Balaenophilidae, supplement (part). An Account of the Crustacea of Norway, with short descriptions and figures of all the species. Bergen Museum, Bergen 5, 369-449.
Schriever, G. (1982) Neue Harpacticoidea (Crustacea, Copepoda) aus dem Nordatlantik II. Vier neue Arten der Familien Diosaccidae and Ameiridae. „Meteor“ Forschungsreise-Ergebnisse D 35, 27–34.
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. Twentieth Annual Report of the Fishery Board for Scotland III, 447–484
Smirnov, S.S. (1946) New species of Copepoda Harpacticoida from the Arctic Ocean. Trudy Dreyfuyuschey Ekspeditsii Glavsermorputi na Ledokole Par. “G. Sedov”1937-1940 3, 231–263. (In Russian)
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 (1/3), 81–109.
Willen, E. (1999) Preliminary revision of the Pseudotachidiidae Lang, 1936 (Copepoda, Harpacticoida). Courier Forschungsinstitut Senckenberg 215, 221–225.
Willen, E. (2000) Phylogeny of the Thalestridimorpha Lang, 1944 (Crustacea, Copepoda). Cuvillier Verlag, 233pp.