Folia Parasitologica, vol. 61 (2014), issue 3

Folia Parasitologica 61[3] 206-212 (2014) | 10.14411/fp.2014.031

Merizocotyle euzeti sp. n. (Monogenea: Monocotylidae) from the nasal tissue of three deep sea skates (Rajidae) in the southwestern Atlantic Ocean

Manuel M. Irigoitia1,3,4, Delfina M. P. Cantatore1, Gabriela E. Delpiani2, Inés S. Incorvaia3, Ana L. Lanfranchi1, Juan T. Timi1
1 Laboratorio de Ictioparasitología, Instituto de Investigaciones Marinas y Costeras (IIMyC-CONICET), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina;
2 Laboratorio de Ictiología, Instituto de Investigaciones Marinas y Costeras (IIMyC-CONICET), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina;
3 Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Paseo Victoria Ocampo, Mar del Plata, Argentina;
4 Comisión de Investigaciones Científicas de la Provincia de Buenos Aires, Argentina

A new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) is described from the nasal tissues of three deep sea rajid skates: the southern thorny skate, Amblyraja doellojuradoi (Pozzi), broadnose skate, Bathyraja brachyurops (Fowler), and yellownose skate, Zearaja chilensis (Guichenot), collected off Buenos Aires Province, Argentina, southwest Atlantic Ocean. Two additional species of sympatric rajid, the white-dotted skate, Bathyraja albomaculata (Norman), and the Patagonian skate, Bathyraja macloviana (Norman), were also examined but no merizocotylines were found. The taxonomy of the Merizocotylinae is not widely accepted and, as a result, the status of Thaumatocotyle and Mycteronastes, and their proposed synonymy with Merizocotyle are currently under discussion. The new species differs from its congeners by having a unique haptoral structure, 6 peripheral loculi that are asymmetrically arranged (one much smaller, indistinctly located in the left or right side of the haptor). The presence of the new species in three sympatric species of Rajidae belonging to distinct genera and subfamilies, as well as its absence in sympatric congenerics indicates the lack of phylogenetic host specificity. Host ecology and geographical distribution appear to be more important than host phylogeny in determining the distribution of this parasite across potential hosts in the region. This constitutes the first record of Merizocotyle in the southwestern Atlantic Ocean.

Keywords: taxonomy, monogeneans, host specificity, Amblyraja doellojuradoi, Bathyraja brachyurops, Zearaja chilensis, Argentina

Received: October 15, 2013; Accepted: December 19, 2013; Prepublished online: March 12, 2014; Published: June 19, 2014


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