In male sharks, pelvic fins bear claspers which are used in copulation.
The male Ascaris has the curled posterior end, while females have a straight posterior end.
Male frogs are distinguished by the presence of sound producing vocal sacs and a copulatory pad on the primary digit of the forelimbs, which are absent in female frogs.
In cockroaches, anal cerci are a pair of appendages at the abdomen end portion, arising from near the 10th segment of the body, present in both males and females. Males have anal style, which is absent in females.