irst recorad of the white prawn Palaemon longirostris H. Milne Edwards, 1837 in the Mediterranean waters of Morocco

In this paper, we provide the first record of the white prawn Palaemon longirostris, a palaemonid shrimp with socio–economic interests, in the northeastern coasts of Morocco, and the third confirmed record for the Mediterranean. Future surveys may increase its known range in the Mediterranean Sea.

Diet analysis indicates seasonal fluctuation in trophic overlap and separation between a native and an introduced shrimp species (Decapoda, Palaemonidae) in the tidal river Thames (U.K.)

The diets of Palaemon longirostris and the non-native P. macrodactylus were investigated to explore their competitive interactions. Both species are largely carnivorous with amphipods being the dominant prey. Chironomid larvae were consumed in large numbers by both species in summer. Vacuity coefficients were higher for both species in winter than summer. A high degree of dietary overlap occurs in winter, with less overlap in summer suggesting that the two species compete for food on a seasonal basis, which may be partly attributed to the absence of chironomid larvae, and generally reduced prey availability, in the winter. If summer prey also become limited then competition for food may increase and P. macrodactylus may then have an adverse effect on P. longirostris. An introduction of P. macrodactylus in the summer, when there is less competition for food, may be more likely to lead to a successful colonisation than one in the winter.