Welcome to G2G forum, Gregorio.
It seems (I think you already have found that out), there are no christening records books nor marriage records books for that time frames in Banome (Otáez, Durango).
The only information I could find on Serapio Núñez is this:
Serapio had 2 younger sisters named Paula (b. ab. 1863) and Otilia (b. ab. 1865). Both of them got married on 1897, according to their marriage records, they both were born in Banome.
The marriage record for Paula can be seen here (record no. 56). The marriage record for Otilia is on the same FamilySearch film in image 350 of 964 (rec. no. 200).