Proteus

Jugovic, Jure, Prevorčnik, Simona, Aljančič, Gregor & Sket, Boris, 2010, The atyid shrimp (Crustacea: Decapoda: Atyidae) rostrum: phylogeny versus adaptation, taxonomy versus trophic ecology, Journal of Natural History 44 (41 - 42), pp. 2509-2533 : 2525

The preliminary observations on feeding efficiency of Proteus

In 21 days after the beginning of our observations, seven and five Troglocaris individuals with long rostra and seven and seven Troglocaris with clipped rostra were eaten by Proteus 1 and Proteus 2, respectively. The time needed for swallowing was measured accurately for 23 out of 26 cases. Although a proper statistical analysis was omitted because of an undersized predator set, the swallowing time of Proteus ( Table 4 ) appeared to be prolonged when feeding on shrimps with long rostra. Proteus 1 needed substantially more time to swallow shrimps with rostra, whereas in Proteus 2 the time difference was minor.

Images recorded with the night vision camera reveal the active attack feeding behaviour of Proteus . Proteus does not chase the prey; it waits till the prey is within its reach to attack it with a quick snap. Without exception, all successful Proteus attacks were accomplished from behind or from the side of the shrimp. Before our recordings we witnessed the frontal attack of Proteus on a shrimp with a long rostrum; its attempt ended after a few moments with the prey spat out. The shrimp survived but was eaten a few days later. Although the snapping-up and spitting-out activity of both Proteus was recorded carefully, the records often did not allow the positive identification of an unsuccessful attack, further removing the possibility of statistical analysis.