Taxonomy and Systematics
The taxonomy of some groups have changed significantly in recent years, especially following the split of several small hermits (P. idaliae, P. atrimentalis and P. striigularis) previously considered subspecies of Phaethornis longuemareus, as well as the split of P. longirostris from P. superciliosus.
Further confusion exists between P. superciliosus and P. malaris: Most taxa previously considered subspecies of the former (bolivianus, insolitus, margarettae, moorei and ochraceiventris) are now placerd with the latter. A fully satisfactory taxonomic treatment of the entire longirostris/malaris/superciliosus group is still lacking according to some Neotropical ornithologists.
Another such case is P. maranhaoensis: Some considered it invalid, believing it was the male plumage of P. nattereri. However, P. maranhaoensis only occurs in the northern part of the range of P. nattereri, and the two have different voices. Molecular work also confirms the validity of P. maranhaoensis, though details presently are lacking. Comparably, P. aethopyga has generally been considered invalid as believed to be a hybrid between P. ruber and P. rupurumii, but this assumption has recently been shown to be incorrect, leading to its revalidation as a distinct species. For the same authors, the taxa proposed as hybrids by Hinkelmann, could be valid taxa, especially P. longuemareus imatacae.
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