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The reproductive biology including insemination frequency, ovarian maturation, gonadosomatic index (GSI), size at Wrst maturity, and fecundity of Melicertus kerathurus were investigated using monthly samples from Thermaikos Gulf. Insemination was recorded by the presence of a spermatophore in the thelycum, and ovarian development was based on macroscopic ovarian staging (ST1-ST5). Inseminated females were found throughout the year with high percentages recorded from April to July. Although all ovarian stages were represented in mated females, insemination increased with size and ovarian maturation. High percentages of vitellogenic or mature ovarian stages were observed from May to July, while immature and developing ovaries were predominant mainly in winter. Spawned ovaries occurred from May to October. Carapace length at Wrst maturity based on the presence of a spermatophore (CL 50sp ) was estimated at 39.20 mm, while that based on the presence of vitellogenic and mature ovaries (CL 50ov ) at 40.70 mm. The seasonal peak in the proportion of mature females (ST4) varied with size. Inseminated females at ST4 and GSI peaked in June-July. GSI varied in relation to insemination status and ovarian stage. In large females (>50 mm CL), the decline in mature ovaries and GSI increment with size indicates a relative reduction in the reproductive output. The number of oocytes ranged from 62,742 to 602,947 (mean § SD: 268,000 § 113,000). As the prawns are targeted during the spawning season, mainly by the artisanal Wshery, and female size at Wrst maturity is selected by artisanal net size, managerial measures toward artisanal Wshery should be implemented.

The Decapoda and Stomatopoda (Crustacea) of the sublittoral zone of Rodos island were studied between 1995 and 2000. Twenty-five sites, at depths ranging from the intertidal to 119 m, were sampled. Three species of stomatopods and 52 species of decapods were identified, bringing the number of decapods known from Rodos to 83. One Stomatopode and nineteen decapods, though previously known from the Aegean Sea, are new records for Rodos. The presence of seven species of Erythrean origin testify to a trend of increasing tropicalization of the area. A remarkable number of Erythrean taxa (fish, Crustacea, Mollusca, Polychaeta) have been established in Rodos, the Dodecanese and the southern Aegean Sea, whereas few reached the northern Aegean and the Ionian Seas. The expansion of the Erythrean species NW of the Levantine Sea is discussed.

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