A new Alloopistholecithum species (Digenea: Lecithasteridae) parasitizing the economically valuable Odontesthes bonariensis (Teleostei: Atherinopsidae)

Abstract

The genus Alloophistolecithum was recently created and comprises species that were previouslyincluded in the genus Lecithaster. The two genera form the subfamily Lecithasterinae. Thegenera includes species that predominantly parasitize marine fish, and occasionally thoseinhabiting fresh or brackish water. This study describes a new species of Alloophistolecithum,which is a parasite of the Argentinian silverside (Odontesthes bonariensis), a fish species thatinhabits brackish waters. Alloophistolecithum magaliae n. sp. is characterized by smooth,unnotched testes; a uterus extending to the posterior end of the body; and short caeca that donot reach the anterior edge of the vitellary. As genetic analyses are currently limited to a fewspecies within the genus, it is premature to establish clear relationships between them. TheArgentinian silverside is considered to be of great economic importance, having spread not onlywithin Argentina but also to other countries for commercial exploitation. The anthropogenicspread of silversides outside their natural range could pose a risk of biological invasion, sostudying their parasitological fauna is important.