Morphological features of the nasal blood fluke XXXX (Schistosomatidae, Digenea) from naturally infected hosts.

@entity4186 @entity22157 @entity21933 @entity281 @entity790
The first author detected the nasal bird schistosome @entity21933 in Iceland in @entity4186 in Landmannalaugar in autumn of 2003. Since then, measurements and morphological studies have been performed on fresh worms (fragments) obtained in the area from naturally infected @entity4186 , A. platyrhynchos and Aythya marila. In the present study, we compare our findings to the original description of @entity21933 by Hor  k et al. (Parasite 5:349-357, 1998) that relies upon worms obtained by experimental infections of A. platyrhynchos f. domestica and @entity22157 f. domestica ducklings. Fragments obtained from naturally infected birds are markedly larger than those obtained in the experimental @entity281 . Also, indistinct sex-related size difference was confirmed; males were more abundant in the material than females. Previously unknown morphological features detected in the present study include, e.g. subterminal spines on the oral sucker directed to the oral opening, spine pattern on the apical part of acetabulum and long tegumental spines (up to 16  m) in the gonad and tail regions of both sexes. In males, we evaluated for the first time the morphology of the cirrus sac enclosing ejaculatory duct, prostata and the entire prostatic region, the course of vas @entity790 . In females, the posterior part of the reproductive system was studied for the first time. The presence of the Laurer's canal was confirmed and its course from the oviduct to the surface, where spermatozoa were noticed to leave the canal, was described.
