First record of black mucus and ocular malformations in the round stingray Urobatis halleri (Rajiformes: Urotrygonidae) at the southern Gulf of California, Mexico

In May–June 2009, thirteen adult individuals of the round stingray Urobatis halleri, with total lengths between 264 and 353 mm, were captured using various fishing gear at La Paz Bay, Baja California Sur, Mexico. The specimens were notable for the presence of ocular malformations, and uniform dark mucus that completely covered the dorsal surface and some portions of the ventral region. These malformations may be a result of one or several factors, including parasitic infection, tumours, or water pollution.