The larval and postlarval development of Parthenope serrata reared in the laboratory and the systematic position of the Parthenopinae (Crustacea, Brachyura).

Abstract

1. Larvae of an oxyrhynchous crab, Parthenope (Platylambrus) serrata (H. Milne Edwards), were successfully reared in the laboratory from hatching to the second crab stage on a diet of Artemia nauplii. Six zoeal stages, one megalopa and the first crab stage are described and illustrated. 2. Two series of larvae were reared at each of two temperatures, 20° and 25° C. The salinity ranged between 34 and 37%. The mortality of the first zoeal stage reduced the initial population to less than half. The first crab stage was attained in approximately 30 days at 25° C, and in 45 days at 20° C, after hatching. The first zoeal stage and the megalopal stage showed more prolonged mean duration than intermediate stages and the pattern of mean duration was similar in both 20° and 25° C. 3. The major characteristics of four species of parthenopid first zoeae of known parentage are tabulated for comparison. The major distinctive characters of Parthenope larvae are presence of rostral, dorsal and lateral spines on the carapace, lunate telson with a dorsally located spine on each fork, normally six zoeal stages, and a smooth "feeler" at the tip of the fifth pereiopod in the megalopa. 4. The number of zoeal stages and the morphological characters are compared to those of oxyrhynchous crabs. The larval characters suggest that Parthenopinae should be removed from the superfamily Oxyrhyncha and placed in the Brachyrhyncha.