Evidence of a landlocked reproducing population of the marine pejerrey Odontesthes argentinensis (Actinopterygii; Atherinopsidae).

In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self-sustaining population has never been recorded.

First report on a pupping area of the tope shark Galeorhinus galeus (Carcharhiniformes, Triakidae) in the south-west Atlantic.

Neonates of the tope shark Galeorhinus galeus are captured in sport and recreational coastal fisheries from January to April each year in Engaño Bay (42° 58'-43° 41' S), Chubut, Argentina. The presence of these neonates is the first evidence of a pupping area for this shark in the south-west Atlantic Ocean. Knowledge of the pupping areas of chondrichthyans is important for establishing conservation measures and appropriate fishing regulations.