Explanation

The key evidence is:

"...decades of meticulous cataloguing that left no documented species, however obscure or seasonally elusive, unrecorded."

This describes a work that is comprehensive, reliable, and the standard reference.

B. definitive means complete, conclusive, and serving as the final authority on a subject.
E. authoritative means highly reliable and respected as an authority.

A. tedious - it may have been tedious to compile, but the sentence is about its reputation, not how interesting it is.
C. verbose - says nothing about excessive wordiness.
D. indiscriminate - means lacking careful judgment, the opposite of "meticulous."
F. superfluous - means unnecessary or redundant, contradicting its esteemed reputation.

Answer: B and E.