Larval and early juvenile development of Tegula eiseni (Jordan, 1936) (Gastropoda: Trochidae)

Abstract

Larval and early juvenile development was studied in Tegula eiseni (Jordan, 1936) for 63 days under laboratory conditions at temperatures of 20 ± 2°C in order to have a photographic sequence of the stages that help identify wild early juvenile specimens. Larvae were obtained by induced spawning. Postlarvae and juveniles were fed Nannochloropsis oculata and Phaeodactylum tricornutum. Elapsed time from fertilization to veliger was 2 days. All larvae settled by day 4. Development of the teleoconch began on day 12. Juveniles (570 ± 60 μm long) had a teleoconch with 11 longitudinal ribs on day 51. On days 58 through 63, the umbilicus and shell spiral provided juveniles with adult-like morphological characteristics (610 ± 60 μm long). We conclude that the identification of early juveniles of this and other associated gastropods coming from wild populations should be performed by selecting those specimens that show a teleoconch in advanced stages to assure a correct identification.