There's no evidence in the OD for the gender of Ilias Bigilala, but both Clements/eBird and IOC have emended the name, to bigilalei and bigilalai respectively as of their most recent versions.
He is "Ilia
h Bigilal
e" in the text (your link), but "
Mr. Il
aia
h Bigilal
e" in the acknowledgements on p. 156
https://www.biodiversitylibrary.org/page/40028929, which seems to make him male.
The normal genitive ending of Latin words that end in -e in the nominative, is either -is (third-declension true Latin words --
mare, -
is, the sea), or -es (first-declension words of Greek origin, originally ending in -η --
poecile, -
es, a known Athenian portico). But these words are not masculine -- the Latin words like
mare are neuter, the Greek ones like
poecile are feminine --, thus treating Bigilale unmodified as a Latin word denoting a man is a bit problematic.
If this name was formed under 31.1.1, the author must be assumed to have set
Bigilal- as the stem of the name, to which he added -
ae instead of -
i as instructed by the article; a masculine equivalent using the same stem would then be
bigilali -- ie, a spelling that differs from both the emended spellings that are in use.
If formed under 31.1.2, the author may have latinized Bigilale into
Bigilala, which, as a word, might be either masculine or feminine (or perhaps into a Greek-like
Bigilales, which would be masculine); the grammatically correct genitive is then (in both cases)
bigilalae, and no emendation should take place.
Why can't an author's choice be respected, if it's not
clearly wrong ?