Growth and reproduction of the deep-water rose shrimp, Parapenaeus longirostris (Lucas, 1846) (Decapoda, Penaeidae), in the southern Tyrrhenian sea.

From June 2006 to May 2007, monthly samples of Parapenaeus longirostris (Lucas, 1846) were collected on land from the landings of two different, although contiguous, fishing grounds exploited by the bottom trawl fisheries of the two fishing harbours of Terrasini and Porticello, located on the north-western coast of Sicily. Carapace length (CL) of the female and male deep-water rose shrimp in Terrasini ranged from 9 to 32 mm and 13 to 26 mm, respectively, whereas in Porticello the length ranged from 8 to 31 mm and 13 to 26 mm, respectively. The Von Bertalanffy Growth Function parameters for Terrasini females and males were CLoo = 38.5 mm, K = 0.65 year(-1) and CL infinity = 32.5 mm, K = 0.85 year(-1), respectively. For Porticello females and males, the parameters were CLoo = 40 mm, K = 0.60 year(-1) and CL infinity = 30 mm, K = 0.76 year(-1), respectively. Analysis of maturity stages indicates that the deep-water rose shrimp is an asynchronous batch of almost continuous spawners, although one to two peaks of activity can be detected. In both fishing areas, the reproductive phase peaked twice, once in January and again from August to September. The sizes at first maturity (CL50%) were 27.8 and 26.6 mm CL for Terrasini and Porticello, respectively.