LABORATORY CULTURE OF THE AEOLID NUDIBRANCH BERGHIA-VERRUCICORNIS (MOLLUSCA, OPISTHOBRANCHIA) - SOME ASPECTS OF ITS DEVELOPMENT AND LIFE-HISTORY

Adult Berghia verrucicornis individuals lay white, spiral egg masses containing zygotes. Egg masses are easily cultured in aerated, Millipore-filtered, seasoned aquarium water. Development proceeds quickly, with the bilobed velum apparent by the end of the second day, and the larval shell appearing at the beginning of the third day after oviposition. Hatching occurs 11 to 12 days after oviposition (23.9 +/- 1.3-degrees-C). If egg masses are incubated without aeration, poecilogonous development is observed; both larvae and juveniles hatch from the same undisturbed egg mass. The larvae metamorphose soon after hatching, losing the velum and larval shell. A habitat-specific inducer is not required for metamorphosis; but a factor associated with the sea anemone Aiptasia pallida appears to enhance a larva's tendency to metamorphose. Juveniles begin feeding on A. pallida three to four days after metamorphosis. Reproductive maturity is achieved as early as 47 days after oviposition. Because B. verrucicornis can be cultured, along with its prey A. pallida, at inland facilities, this nudibranch species may be a useful model for laboratory-oriented life history and neurobiological investigations.