abstract:A nuptial pad (or thumb pad, nuptial excrescence, nuptial ball) is a secondary sex characteristic present on some mature male frogs and salamanders. Triggered by androgen hormones, this breeding gland (a type of mucus gland) appears as a spiked epithelial swelling on the forearm and prepollex that aids with grip, used primarily by males to grasp (or clasp) females during amplexus.