Parasitisation by Bathycreadium elongatum ­(Digenea, Opecoelidae) in pyloric caeca of Trachyrincus scabrus (Teleostei, Macrouridae)

Raphidascaris ( Raphidascaris ) macrouri n. sp. (Nematoda: Anisakidae) from two deep-sea macrourid fishes in the Western Mediterranean: Morphological and molecular characterisations

“…Most efforts have been focused on the identification and taxonomy of parasites in a range of deep-sea fish hosts in the Western Mediterranean [1][2][3][4][5][6][7]. Two common inhabitants of the western Mediterranean middle-slope [8,9] are Nezumia aequalis (Günther) and Trachyrincus scabrus (Rafinesque) (Gadiformes: Macrouridae), demersal deep-sea fishes distributed in the Atlantic Ocean and Mediterranean Sea [10].…”

Annual variation of parasite communities of deep-sea macrourid fishes from the western Mediterranean Sea and their relationship with fish diet and histopathological alterations

“…The granulomatous inflammatory reaction in the mesentery of the pyloric caeca of T. scabrus has already been described in this species (Constenla et al, 2011), being more prevalent in spring as in the present work. This alteration appears to be a consequence of a particular process of passive release of digenean parasites (with higher abundances during this season) and other material within pyloric caeca to the abdominal cavity due to the fragility of the apex of this organ in this species (Constenla et al, 2011).…”

“…All parasites found in the present work are new data for these host species in this area (see also Constenla et al, 2011;Pérez-del-Olmo et al, 2014;Pérez-i-García et al, 2015b). Furthermore, ten parasites (the digenean Steringotrema sp., the cestodes Tetraphyllidea gen. sp.…”

“…This alteration appears to be a consequence of a particular process of passive release of digenean parasites (with higher abundances during this season) and other material within pyloric caeca to the abdominal cavity due to the fragility of the apex of this organ in this species (Constenla et al, 2011). The morphology and structure of CUEs are similar to those described by MacKenzie (1979) in Micromesistius poutassou and in many other species of gadoids and other species (MacLean et al, 1987;Munday and Brand, 1992;Nowak, 1996;Nowak et al, 2004) and are reported for the first time in N. aequalis and T. scabrus.…”

“…However, the knowledge on the parasite fauna of H. italicus, N. aequalis and T. scabrus in the Mediterranean Sea is almost inexistent, since so far just a single digenean, Bathycreadium brayi (see Pérez-del-Olmo et al, 2014) (syn. Bathycreadium elongatum of Constenla et al (2011)), has been described in T. scabrus from the western Mediterranean basin. Knowledge of the parasite fauna of the Mediterranean macrourids is of special interest because they (as all members of the deep-sea fauna, Pérès, 1985) exhibit low species richness and thus offer few potential hosts to parasites.…”