Schemes including Agkistrodon contortrix

• IUCN Red List of Threatened Species. Version 2012.1 Agkistrodon contortrix
• The Reptile Database (Agkistrodon_contortrix) Agkistrodon contortrix
• IUCN Red List of Threatened Species. Version 2012.2 (64297) Agkistrodon contortrix
• NatureServe Explorer: An online encyclopedia of life. Version 7.1 (ELEMENT_GLOBAL.2.103250) Agkistrodon contortrix
• CONABIO (15826REPTIB501112) Agkistrodon contortrix
• GBIF (2444638) Agkistrodon contortrix