clasper

[ klas-per, klah-sper ]

/ ˈklæs pər, ˈklɑ spər /

a person or thing that clasps.

(in insects, fishes, crustaceans, etc.) one of the modified, usually paired organs or parts by which the male clasps the female during copulation.

Origin of clasper

First recorded in 1545–55; clasp + -er¹

The pelvic fins in the male bear long grooved cartilaginous rods which are accessory copulatory organs or claspers.

The Vertebrate Skeleton |Sidney H. Reynolds
It has a hump on the back of the seventh segment, and two more on the ninth, and possesses four pairs of claspers.

Butterflies and Moths |William S. Furneaux
This one also has humped segments, and the claspers of the thirteenth segment are imperfectly developed.

Butterflies and Moths |William S. Furneaux
The caterpillars of this family usually have humps on the sixth and twelfth segments only, and have two pairs of claspers.

Butterflies and Moths |William S. Furneaux

Its mouth and jaws have quite disappeared, and the legs and claspers are apparently gone.

Butterflies and Moths |William S. Furneaux

claspers

/ (ˈklɑːspəz) /

a paired organ of male insects, used to clasp the female during copulation

a paired organ of male sharks and related fish, used to assist the transfer of spermatozoa into the body of the female during copulation