Heloderma exasperatum

The Rio Fuerte beaded lizard ("Heloderma exasperatum") is a venomous species of beaded lizard in the family Helodermatidae. It is found in the tropical forests and shrublands of Western Mexico, specifically around the Rio Fuerte and Rio Mayo basins. They are often found in or near abandoned mammal burrows and sources of water. 
Description.
Adult beaded lizards range from 60 to 90 cm (23.6 to 35.4 in) in length. They can weigh up to 4,000 grams (8.8 lb). It is very similar to the Mexican beaded lizard in appearance and size.
Taxonomy.
The Rio Fuerte beaded lizard is a member of the family Helodermatidae. It was formerly considered a subspecies of the Mexican beaded lizard, whom which is its closest living relative, but has been elevated to full species status in 2013.
Etymology.
The generic name, "Heloderma", means "studded skin", from the Ancient Greek words hêlos (ηλος), meaning "the head of a nail or stud", and derma (δερμα), meaning "skin".
The specific name, "exasperatum", means "completely rough" in Latin.