Table 1 Description of outcomes for database queries

A read query from taxon A returns a match from taxon A

True match (we correctly infer taxon A is present)

M_true

A read query from taxon A returns a match from a taxon that is not A

False match (we infer taxon A is absent due to a secondary match)

M_false

A read query from taxon A returns no hit at all

Failed query (we infer taxon A is absent due to database paucity).

M_fail