Egg capsules and veligers of the corallivorous muricid gastropod Drupella rugosa (Born, 1778)

Population outbreaks of the corallivorous muricid gastropod Drupella can cause significant coral mortality but our current understanding of their early life history, recruitment mechanisms and behaviour is limited. In this study, we observed the deposition of D. rugosa (Born, 1778) egg capsules on bare skeletal surfaces of the scleractinian coral Pocillopora acuta Lamarck, 1816. Each egg capsule measured 2.43 by 2.39 mm and contained an average of 67 embryos. Intracapsular development lasted 15 days post-oviposition, after which free-swimming veliger larvae emerged from the capsule. The larval shells of these veligers with 1⅓ whorls averaged 328 by 245 μm in size. Compared to its congeners, D. rugosa veliger larvae were the largest at hatching. Detailed descriptions of D. rugosa egg capsules and early veligers are provided to supplement current knowledge on reproductive biology and early life history of the species. Such data will provide more insights into understanding and modelling the population dynamics of D. rugosa.

以珊瑚为食的核果螺属（Drupella）腹足类的种群暴发可造成珊瑚大量死亡，但目前学界对其早期生活史、种群补充机制与行为特征的认知仍较为有限。本研究观察到，皱唇核果螺（D. rugosa, Born, 1778）的卵囊会附着于尖枝鹿角珊瑚（Pocillopora acuta Lamarck, 1816）的裸露骨骼表面。单个卵囊尺寸为2.43×2.39毫米，平均内含67枚胚胎。囊内发育时长为产卵后15天，此后自由游泳的面盘幼虫（veliger larvae）破囊而出。这类面盘幼虫的幼虫壳具1又1/3螺层，平均尺寸为328×245微米。与其同属物种相比，皱唇核果螺的孵化面盘幼虫体型最大。本研究详细描述了皱唇核果螺的卵囊与早期面盘幼虫，以补充该物种生殖生物学与早期生活史的现有认知。此类数据将为深入理解皱唇核果螺的种群动态并构建其种群动态模型提供更多参考依据。