Beyond the sea: Crepidula atrasolea as a spiralian model system.

This paper introduces the black-footed slipper snail, Crepidula atrasolea, as a new model for biological studies in the Spiralia. C. atrasolea is a calyptraeid gastropod, and congener of the Atlantic slipper snail, C. fornicata. Like C. fornicata, C. atrasolea shares a sedentary, filter-feeding, protandrous lifestyle, but is preferable as a developmental model because of its short generation time, year-round reproduction, and direct development. In our lab, individuals go from egg to reproductive females in under six months, as compared to an estimated 1-2 years for C. fornicata. Here we provide details for collecting and transporting animals, setting up inland aquaria, and maintaining laboratory colonies of C. atrasolea. We also describe early development, which is similar to that in other calyptraeids. Females brood encapsulated embryos for three weeks, which hatch as "crawl-away" juveniles. We also present a developmental transcriptome for C. atrasolea, covering early cleavage through late organogenesis stages, as a useful tool for future studies of gene expression and function. We provide this information to the broader developmental community to facilitate widespread use of this system.