I guess we could simply disregard the reference to Drapiez ?
Gray's action in the 1849
Appendix was to add "
Picus Lewis Drap." to the synonymy of
"M[elanerpes].
torquatus", as used on
p. 444 of his work, where he also provided references to descriptions and illustrations of "M.
torquatus (Wils.)" by Bonaparte and Audubon. I assume these references can be seen as indications making the name available (satisfying
ICZN 12.2.1 and 12.2.7).
Note that a name first introduced in the synonymy of an available name is not regarded under the current Code as having thereby been made a
nomen novum for that available name.
Such a name is available from its original introduction in synonymy only if it was "treated before 1961 as an available name and either adopted as the name of a taxon or treated as a senior homonym" (
ICZN 11.6.1).
Its type series "consists of the specimen (or specimens) cited with that name in the published synonymy, or, if none was cited there, denoted by that name when it was adopted as the name of a taxon." (
ICZN 72.4.3), and is not inherited from the name in the synonymy of which it was originally placed.
In the present case, Gray did not cite any specimen with the name.
Riley 1905 proposed to use
Asyndesmus lewisi for the species, but this was after a discussion that concluded that,
Picus collaris Wilson being preoccupied, the species was left "without a name" : I would read it as the proposal of a new name authored by Riley himself, not as an adoption of an emended version of Gray's "
Picus lewis Drap.". Subsequently (e.g.,
Ridgway 1914), this name was cited as
Asyndesmus lewisi Riley 1905. The first real adoption of Gray's
Picus Lewis as the valid name of a taxon may have been in the
1931 ed. of the AOU Checklist. (There, the name was treated as a new name for
P. torquatus Wilson, which probably can be read as making the type specimen of this last name "denoted" by Gray's name in the Checklist, hence the type of Gray's name as well ?)