Proposal (435) to South American Classification Committee

Place Deconychura stictolaema in a new genus Certhiasomus

Effect on SACC: Deconychura stictolaema would become Certhiasomus stictolaema and would be moved in the linear sequence.

Background & New information (much copied from Derryberry et al. 2010 – RTB):

As part of a project to reconstruct the species level phylogenetic relationships of the Furnariidae and Dendrocolaptidae from DNA sequences (mitochondrial and nuclear), Derryberry et al. (2010) determined conclusively that D. longicauda and D. stictolaema are not sister taxa. Instead, D. stictolaema is sister to a clade composed of D. longicauda, Sittasomus griseicapillus, and the genus Dendrocincla (six species) (see figure below).

Derryberry et al. considered two taxonomic options for addressing the polyphyly of Deconychura: (1) merging Dendrocincla, Sittasomus, and Deconychura into a single expanded genus, or (2) erecting a new genus for D. stictolaema. Through a morphometric analysis, they determined that combining Dendrocincla, Sittasomus, and Deconychura into a single genus would result in a clade far more morphologically heterogeneous than any other genus in the Dendrocolaptidae. Thus, they described a new genus for D. stictolaema: Certhiasomus. As can be seen from the figure below, Certhiasomus is the sister to a group of genera that consists of Dendrocincla, Deconychura, and Sittasomus, and thus should precede these three genera, and the positions of Sittasomus and Deconychura should be reversed according to the relationships shown in the figure, as follows:

Certhiasomus stictolaema Spot-throated Woodcreeper

Dendrocincla tyrannina Tyrannine Woodcreeper

Dendrocincla fuliginosa Plain-brown Woodcreeper

Dendrocincla merula White-chinned Woodcreeper

Dendrocincla homochroa Ruddy Woodcreeper


Sittasomus griseicapillus Olivaceous Woodcreeper

Deconychura longicauda Long-tailed Woodcreeper

References

Derryberry, E., S. Claramunt, R. T. Chesser, A. Aleixo, J. Cracraft, R. G. Moyle, and R. T. Brumfield. 2010. Certhiasomus, a new genus of woodcreeper (Aves: Passeriformes: Dendrocolaptidae). Zootaxa 2416:44-50.

Figure from Derryberry et al. (2010)

Robb T. Brumfield, April 2010

Comments from Nores: “YES. Parece mucho más lógico crear el nuevo género Certhiasomus antes que unir Deconychura longicauda con Sittasomus y Dendrocincla. No obstante, no me terminan de convencer todas las combinaciones y separaciones que resultan de los análisis moleculares. Por ejemplo, como yo puse en la propuesta # 430 en el árbol resultante de los análisis moleculares de Trogon (DaCosta y Klicka 2008) en el primer clado, ramonianus es sister del clado compuesto por violaceus, curucui y surrucura, pero en la parte inferior del clado hay especímenens del eEcuador (=ramonianus) que es sister de otro de Costa Rica, Honduras, Mexico y Panama (=caligatus).”

Comments from Stotz: “YES. Seems like a much better solution than a large Dendrocincla.”