Redescription of Eight Species of Parasitic Copepods (Siphonostomatoida, Pandaridae) Infecting Japanese Elasmobranchs.

Eight species of pandarid copepods are redescribed based on specimens recovered from six species of Japanese elasmobranchs. These are Pandarus cranchii Leach, 1819, P. smithii Rathbun, 1886, Gangliopus pyriformis Gerstaecker, 1854, Pseudopandarus gracilis Kirtisinghe, 1950, Dinemoura latifolia (Steenstrup & Lütken, 1861), Echthrogaleus coleoptratus (Guérin-Méneville, 1837), E. denticulatus Smith, 1874, and Nesippus orientalis Heller, 1868. In P. cranchii, both sexes of copepodid IV and V are described, one of them retains the frontal filament. The postnaupliar juveniles preceding the adult are referred to here as copepodid stages instead of chalimus. The presence of the postantennal process was verified in all species here dealt with, though it is replaced by an additional adhesion pad in D. latifolia. The depression, seemingly acting as the sucker, was found in N. orientalis on the female leg 3 basis. [ABSTRACT FROM AUTHOR]