Biffando de la Tanén was accidentally caught in a net when Marty was trying to catch a frog. But when Doc apologized for the net and explained that they were looking for a frog, he assumed that they were looking for the Lost City of Gold, which belonged to the nearby incan people.
In terms of chronology, Biffando is the first Tannen to be shown after Biffingham of Tannenshire, even though there is at least 200 years of Tannen family history between them not shown within the animated series.
Biffando also resembles the Spanish explorer Fransisco Pizzaro, who came to South America during the 1530's, the same time as Biffando and his group of conquistadors did. It is unknown how the Tannen family had a series of relatives in Spain, when clearly with Biffingham, and even earlier with Bifficus, the Tannen family started in Rome, and moved to England, an enemy of Spain for many years.