Table 4. Importance index (I _x) from the composition of prey found in Bothrops asper from Ecuador.

	n x	n x %	f x	f x %	m x	m x %	I x
Scolopendromorpha	6	8.7	4	8.3	10.2	3.7	6.9
Anura	11	15.9	7	14.6	15.9	5.7	12.1
Squamata	3	4.3	2	4.2	9.9	3.6	4.03
Mammalia	49	71.01	35	72.9	240.2	86.9	76.9

Note:

n_x, abundance of prey item by taxonomic classification; f_x, frequency of the type of prey x; m_x, mass of each complete prey item by taxonomic classification. %, percentage for each category. Abundance and frequency indexes calculated based on all identifiable prey items (n = 69), mass based on complete preys only (n = 22). Adapted from Biavati, Wiederhecker & Colli (2004).