Fossil shrimps more than 220 million years old (Upper Triassic, Norian) have been found in the Forni Dolomite, in Carnia, in the province of Udine: their names are Dusa longipes, Antrimpos noricus and Acanthinopus gibbosus. Among them, the most common species is D. longipes: in fact, thousands of remains have been found, including several complete or nearly complete specimens such as the ones on exhibit in the museum. Based on the shape of the claws and the gracility of the walking limbs, it has been suggested that Dusa either fed on organic debris or were necrophagous. The gracility of the limbs also indicates that they lived in rather calm waters. Concentrations of complete exoskeletons have been identified along the Rio Seazza (Preone) valley, possibly due to mass die-offs, suggesting that these decapods were gregarious and lived in large swarms.
