I am currently working on the meriofauna (63 - 2000 microns) on the calcareous algae Corallina officinalis in west Wales. I am at some sites turning up numerous spirorbids. This is a group new to me (my background is in foraminifera). Can anybody help me give names to my two species? They are shown in the attached photograph. I had initially thought they might be Spirorbis corallinae and S. tridentatus, but the coiling direction is wrong.