 For many years Odontogriphus ( " toothed riddle " ) was known from only one specimen , an almost featureless oval smear on a slab , with hints of tiny conical teeth . However , 189 new finds in the years immediately preceding 2006 made a detailed description possible . It had a pair of slightly V @-@ shaped tooth @-@ rows just ahead of the mouth , very like Wiwaxia ′ s . This pitched Odontogriphus into the middle of the debate about whether Wiwaxia was closer to the mollusc or the annelid lineage , resulting in a frank exchange of views . 
