Proposal (486) to South
American Classification Committee
Restore Xenops
milleri to the genus Microxenops
In naming the new genus Microxenops,
Chapman (Chapman 1914) commented “Doubtless it resembles Xenops
in habits, as it does in general appearance, but the marked difference in their structure suggests that the resemblance is superficial rather than indicative of close relationship.”
Chapman was correct. Two molecular studies, Moyle et al. (Moyle et al. 2009) and Derryberry et al. (in press) demonstrate conclusively that Xenops
milleri is not closely related to the clade containing all other Xenops. X. milleri occurs
as a long branch that is sister to a clade containing Pygarrhichas and Ochetorhynchus. The other Xenops occur as the basal clade to all other furnariids.
I propose restoring the genus Microxenops for Xenops milleri.
Literature Cited
Chapman, F. M. 1914.
Descriptions of a new genus and species of birds from Venezuela. Bulletin of
the American Museum of Natural History 33:193-197.
Derryberry, E. P., S. Claramunt, G.
Derryberry, R. T. Chesser, J. Cracraft, A. Aleixo, J. Pérez-Emán, J. V. Remsen
Jr., and R. T. Brumfield. in press. Lineage diversification and morphological
evolution in a large-scale continental radiation: the Neotropical ovenbirds and
woodcreepers (Aves: Furnariidae). Evolution.
Moyle, R. G., R. T. Chesser, R. T.
Brumfield, J. G. Tello, D. J. Marchese, and J. Cracraft. 2009. Phylogeny and
phylogenetic classification of the antbirds, ovenbirds, woodcreepers, and
allies (Aves: Passeriformes: infraorder Furnariides). Cladistics 25:386-405.
Robb
Brumfield, June 2011
Comments from Remsen: “YES. This is another one of those Peters Era lumps that never
should have happened. As noted in
my HBW chapter, the only thing this bird shares with true Xenops is the wing band – it lacks the distinctive tail
pattern, the conspicuous malar mark, the laterally compressed bill, and the
dead-twig-hammering behavior of Xenops.”
Comments from Stiles: “YES. I agree that milleri
is certainly an oddball in Xenops; a
monotypic genus emphasizes its distinctness.”
Comments from Nores: “YES. For reasons succinctly laid out in the proposal, it is evident that Xenops
milleri is not closely related to the clade containing all other Xenops.”
Comments
from Pacheco:
“YES. O restabelecimento de Microxenops prova ser uma apropriada
medida.”
Comments from Zimmer: “YES. Two
sets of molecular data now provide evidence corroborating what many of us have
felt all along regarding not only morphological differences between milleri and the rest of Xenops, but also vocal differences,
which are perhaps even greater.”
Comments from Pérez-Emán: “YES. This taxon is clearly different
from Xenops both in molecular and
morphological grounds.”