By Thomas Pape
Generally no. The page, or position on a page, on which a name (or act) appears does not in itself influence its precedence relative to other names (or acts) in the same work.
The valid name of a taxon is the oldest available name applied to it, unless this name is invalidated by one of the provisions of the Code or by a ruling by the Commission. Thus, the precedence, i.e., the order of seniority of available names or nomenclatural acts, is determined by the dates on which the works containing the names or acts were published. If two names that are found to be synonyms were published in the same work, they are simultaneously published and equally old (unless the work was issued in parts at different dates and with the names in different parts).
The order of precedence of simultaneously published names or acts is determined by the first reviser or by a ruling of the Commission using its plenary power. The first reviser is that author who first selects one of two (or more) simultaneously published names considered synonymous (or different original spellings of the same name) to have precedence over the other name(s).
The one exception (recommendation 69A.10) is that when designating the type species for a genus, all other things being equal (i.e. a choice cannot be made on the basis of recommendations 69A.1-9), an author should give preference to the species cited first in the work, page or line. This is known as “position precedence”.