Thanks for the good details Laurent and for putting me straight! I noticed the issue with the "u" instead of a "o", and I made a wrong assumption that the error (or "disconformity"?) could have been somehow intentional from Bonaparte, but obviously this doesn't make any sense (and I should leave these complicated issues for specialists like you to deal with). What is the current consensus on the true etymology of the genus name?So we have two candidate etymologies, then ?
Although it is true that the bird is nowhere directly compared to Pyrrhula, I don't really see anything in the original texts, either, suggesting that πυρρός ("fire red") played a direct role in the creation of this name. [πυρρός + loxia] would not account for the u in Pyrrhuloxia.
In the Conspectus, the subgenus Pyrrhuloxia is described as "Rubro colore tantum indutus !", which means something like "Only adorned with red colour !", and is obviously intended to have a counterpart in "Color (maris) ruberrimus !" ("Colour (of male) extremely red !"), which characterises subgenus Cardinalis. I.e., if anything, Pyrrhuloxia would seem to be described as not-very-red in comparison to its putative closest relative.