corrugator cutis muscle of anus

cor·ru·ga·tor cu·tis mus·cle of a·nus

muscle of anal triangle with muscle fibers radiating from the superficial portion of the external sphincter to the deep aspect of the perianal skin, said to cause puckering of that skin, which contributes to the air/water-tight "seal" of the anal canal. Synonym(s): musculus corrugator cutis ani