Nuptial pad

Nuptial pad (arrow) on thumb of Pelophylax esculentus

A nuptial pad (also known as thumb pad, or nuptial excrescence[1]) is a secondary sex characteristic present on some mature male frogs and salamanders.[2][3][4][5] Triggered by androgen hormones, this breeding gland (a type of mucous gland) appears as a spiked epithelial swelling on the forearm and prepollex that aids with grip, which is used primarily by males to grasp (or clasp) females during amplexus.[6] They can also be used in male–male combat in some species.[6]

  1. ^ William E. Duellman; et al. (1994). Biology of Amphibians. JHU Press. p. 55. ISBN 978-0-8018-4780-6.
  2. ^ "Science & Nature – Wildfacts – Common frog, grass frog". BBC. 2008-07-25. Retrieved 2011-07-14.
  3. ^ "Mertensiella caucasica". AmphibiaWeb. 1999-10-03. Retrieved 2011-07-14.
  4. ^ "Ommatotriton ophryticus". AmphibiaWeb. 2005-10-26. Retrieved 2011-07-14.
  5. ^ "Pleurodeles waltl". AmphibiaWeb. 2002-05-25. Retrieved 2011-07-14.
  6. ^ a b F. Harvey Pough; Andrews RM; Cadle JE; Crump ML; Savitsky AH; Wells KD (2004). Herpetology (3rd ed.). Upper Saddle River, NJ: Pearson/Prentice Hall. pp. 67–68. ISBN 0-13-100849-8.