I here comment on the phylogenetic position and generic status of the rare and threatened Abbott's Booby Papasula abbotti. I argue that the current genus name of this species was erected from an incorrect interpretation of a phylogenetic hypothesis and a straightforward decision about its generic placement cannot be made, given the conflicts regarding the species' closer phylogenetic relationships. Methods: I examined three published hypotheses of phylogenetic relationships for Sulidae (one

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... d on phenotypic and two on molecular data), following Hennig's principle of reciprocal illumination, wherein a given hypothesis is evaluated by the extent to which it agrees with competing hypotheses. Results and discussion: There is a considerable degree of congruence among the examined cladograms, the main conflict being the position of Abbott's Booby. Therefore, for the time being, I propose that in any cladistic-based classification the name 'Sula abbotti' be placed at the level at which their relationships are more surely determined (i.e., below the family name and above Sula and Morus and labelled as 'incertae sedis') or the name Papasula be considered as a subgenus.