Cenchritis muricatus (beaded periwinkle snails) Bahamas

Description:

Summary.mw-parser-output table.commons-file-information-table,.mw-parser-output.fileinfotpl-type-information{border:1px solid #a2a9b1;background-color:#f8f9fa;padding:5px;font-size:95%;border-spacing:2px;box-sizing:border-box;margin:0;width:100%}.mw-parser-output table.commons-file-information-table>tbody>tr,.mw-parser-output.fileinfotpl-type-information>tbody>tr{vertical-align:top}.mw-parser-output table.commons-file-information-table>tbody>tr>td,.mw-parser-output table.commons-file-information-table>tbody>tr>th,.mw-parser-output.fileinfotpl-type-information>tbody>tr>td,.mw-parser-output.fileinfotpl-type-information>tbody>tr>th{padding:4px}.mw-parser-output.fileinfo-paramfield{background:#ccf;text-align:right;padding-right:0.4em;width:15%;font-weight:bold}.mw-parser-output.commons-file-information-table+table.commons-file-information-table,.mw-parser-output.commons-file-information-table+div.commons-file-information-table>table{border-top:0;padding-top:0;margin-top:-8px}@media only screen and (max-width:719px){.mw-parser-output table.commons-file-information-table,.mw-parser-output.commons-file-information-table.fileinfotpl-type-information{border-spacing:0;padding:0;word-break:break-word;width:100%!important}.mw-parser-output.commons-file-information-table>tbody,.mw-parser-output.fileinfotpl-type-information>tbody{display:block}.mw-parser-output.commons-file-information-table>tbody>tr>td,.mw-parser-output.commons-file-information-table>tbody>tr>th,.mw-parser-output.fileinfotpl-type-information>tbody>tr>td,.mw-parser-output.fileinfotpl-type-information>tbody>tr>th{padding:0.2em 0.4em;text-align:left;text-align:start}.mw-parser-output.commons-file-information-table>tbody>tr,.mw-parser-output.fileinfotpl-type-information>tbody>tr{display:flex;flex-direction:column}.mw-parser-output.commons-file-information-table+table.commons-file-information-table,.mw-parser-output.commons-file-information-table+div.commons-file-information-table>table{margin-top:-1px}.mw-parser-output.fileinfo-paramfield{box-sizing:border-box;flex:1 0 100%;width:100%}} Description: Tectarius muricatus (Linnaeus, 1758) - beaded periwinkle snails on phytokarst. These snails are on a phytokarst surface of aragonitic calcarenite limestones of the Hanna Bay Member (upper Rice Bay Formation, middle to upper Holocene). They are supratidal rocky shore bacteria/algae grazers. The jagged, pitted rock surface is phytokarst, formed by limestone being subjected to slow, partial dissolution by the life activities of bacteria and algae that coat the surfaces (= dark gray films). The snails are feeding on these biofilms by using their radulas to scrape away at the substrate. Phytokarst is one type of epikarst - limestone dissolution features at the top of the vadose zone. Classification: Animalia, Mollusca, Gastropoda, Littorinidae Locality: rocky cliffs along southern shoreline of Graham’s Harbour, just west of Bahamas Field Station, northern margin of San Salvador Island, eastern Bahamas. Date: 19 June 2010, 07:38. Source: Tectarius muricatus (beaded periwinkle snails) on phytokarst (San Salvador Island, Bahamas) 4. Author: James St. John.