Pseudocapillaria (Pseudocapillaria) moraveci sp. n. (Nematoda: Capillariidae) from the stomach of Gobius paganellus (Perciformes: Gobiidae) from Vigo estuary (NW Spain).

Pseudocapillaria moraveci sp. n. (Nematoda, Capillariidae) is described from the stomach of Gobius paganellus Linnaeus (Perciformes, Gobiidae) from rocky shores of the Vigo estuary (Northwest Atlantic coast of Spain). Scanning electron microscopy reveals the absence of a dorsal cuticular membrane interconnecting the caudal lobes of male, thus confirming the assignment of this new species to the nominotypical subgenus Pseudocapillaria Freitas, 1959. Pseudocapillaria moraveci can be easily differentiated from other marine congeneric species belonging to subgenera Pseudocapillaria and Ichthyocapillaria Moravec, 1982 by its muscular oesophagus, which is distinctly thickened at the distal third, the terminal or almost terminal anus in female, the presence of a basal internal papilla on each ventrolateral caudal lobe in male, and its exclusive site preference for the stomach. In addition, the spicule, which measures 0.180-0.292 mm in length (4.9-7.9% of body length) and possesses a proximal end expanded and oblique in lateral view, a narrowed middle part, and a distal end almost pointed, also distinguishes this species. Pseudocapillaria moraveci is, together with P. tomentosa (Dujardin, 1843) Moravec, 1987, the only species in the genus Pseudocapillaria that has been reported to infect members of the family Gobiidae.