Cathaemasia hians (Trematoda: Cathaemasiidae) infecting black stork nestlings (Ciconia nigra) from central Spain.

The trematode Cathaemasia hians is recorded for the first time in nestling Black storks, and for the first time in Black storks in Spain. The parasite was found in the upper part of the oesophagus of Black storks (Ciconia nigra). Presence of this parasite in three nestlings raises the possibility of completion of the parasite's life cycle in Europe. In addition, a sub-adult bird recuperating from bone fractures was also found to be infected. C. hians is apparently absent from the more common white stork (Ciconia ciconia) from the same area. The different feeding behaviour of the two species of storks may account for this.