Description Phalacroma rapa has a bulbous protrusion at the posterior end of the sulcus (arrows), as opposed to the more straight sulcus of P. mitra.Author Larsen, Jacob· PNG file - 196.41 kB - 580 x 262 pixelsadded on 2010-10-121 601 views This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License