Selective Settlement of the Planktonic Larvae of the Epizoic Limpet Lottia tenuisculpta (Patellogastropoda: Lottiidae)

Abstract

The epizoic lottiid limpet Lottia tenuisculpta uses tegulid and muricid snails as hosts in its juvenile period. However, it is unclear when and how it finds its host species. To clarify the timing of attachment to the host shells, larval settlement was experimentally induced under controlled conditions. Between January and February 2017, mature L. tenuisculpta were collected from rocky shores around the Seto Marine Biological Laboratory, Japan. Planktonic larvae were prepared using artificial fertilization methods. Four small plastic plates, each covered with benthic diatoms and treated with tegulid host mucus, muricid host mucus, conspecific adult mucus, and a control were hung in beakers as settlement substrates with a certain amount of veliger larvae and filtered seawater. After 24 h, the metamorphosed larvae were counted on each plate. The number of settled larvae was significantly higher on the mucus of the tegulid host than on the control. This result suggests that the larvae of L. tenuisculpta are attracted to their host species by their mucus and may settle on the host shells directly.