Puesta y desarrollo de Ascobulla fragilis (Jeffreys, 1856) (Opisthobranchia, Sacoglossa)

The egg masses of Ascobulla fragilis consist of a gelatinous mass, usually C-shaped, whose inside part contains a cord of egg capsules inter-connected by a chalaza. The egg capsules measure about 150 μm wide and 180 μm long. The uncleaved eggs measure about 55 μm in diameter. The chronology and photographs of major developmental events are provided. Larval development is planktotrophic and veligers hatch on the sixth day after egg deposition. At this time of the hatching the veliger measure 125 μm and the larval shell measure 100 μm. Metamorphosis has not been observed.