Early life cycle and effects of microalgal diets on larval development of the spiny rock-scallop, Spondylus limbatus (Sowerby II, 1847)

Spondylids of Eastern Pacific Ocean

“…Postlarval stages may remain as freeliving benthonic organism until final cementation on hard substrates when shell size is 2-3 mm (2-3 mo). The cemented postlarvae continued their growing, reaching a 14 mm after 6 mo from the postlarvae settlement (Loor et al 2016) (Fig. 7).…”

“…A provinculum is highly noticeable at 3-day-old larvae sizing 120 mm, when the veliger larvae turned markedly umboned (150 mm/day 8). The eyespots are formed when the larvae reach 165 mm (day 10) and crawling pediveligers with a double ring on the shell edges appear on day 12 in larger sized larvae (185 mm), when the pelagic phase is finished , Loor et al 2016 (Fig. 6).…”

“…Energetic resources for gonadal maturation are allocated on the adductor muscle throughout winter and spring (VillalejoFuerte et al 2002, Cudney-Bueno & Rowell 2008. This is a broadcast spawner and its early life cycle was described under laboratory conditions , Loor et al 2016. The fecundity, estimated by counting oocytes (60 mm) after spawning induction, varies between 1.5 and 72 3 10 6 oocytes, depending on size and reproductive condition of the individual ).…”

“…These animals have been reared at density of one adult per 25 l in a flow-through system with an exchange rate of 2 l/min (partial exchange of 6.4 times per day) ) and fed on Tisochrysis lutea (T-ISO) and Chaetoceros calcitrans (clone C-CAL) at an average algae concentration of 150 cells/ml (ratio: 1:1). Loor et al (2016) reared 1 adult per 100 l with a 25% of daily water exchange and fed on an algal mixture of Chaetoceros gracilis and T. lutea (ratio: 2:1 in cells number) provided daily at a mass dry algal weight equivalent to a 5% of broodstock dry meat weight in tanks.…”

“…Removal of such organisms is laborious, time consuming, and unnecessary. Adult animals can be maintained in flow-through or batch systems during the acclimation, reproductive conditioning, and spawning induction process , Loor et al 2016.…”