 The pectoral fin disc of the onefin electric ray is wider than long and almost circular in shape . The two large , kidney @-@ shaped electric organs are visible beneath the skin on either side of the head . The eyes are small and protruding ; the larger spiracles lie closely behind and have three small finger @-@ like projections on their rims . The nostrils are placed rather close together , and between them is a long skirt @-@ like flap of skin that reaches the mouth . The small and protrusible mouth is nearly straight and surrounded by prominent furrows . The teeth are tiny and pointed . There are five pairs of small gill slits on the underside of the disc . 
