Recognize a new genus Pseudasthenes for some members of Asthenes
Effect on SACC: Four Asthenes species would be included in the new genus Pseudasthenes. New names would be P. humicola, P. patagonica, P. steinbachi, and P. cactorum.
Background & New information (much of this was copied from Derryberry et al. 2010 --RTB):
A recently published phylogeny of the Furnariidae provided the first genetic evidence of lack of monophyly in Asthenes (Irestedt et al. 2006). This phylogeny included two species of Asthenes, one of which—A. cactorum (Cactus Canastero) —was sister to Pseudoseisura, whereas the other—A. urubambensis (Line-fronted Canastero) —formed a clade with Oreophylax and Schizoeaca. Gonzalez and Wink’s (2008) phylogeny of the Synallaxinae included three species of Asthenes. They found that A. cactorum and A. humicola (Dusky-tailed Canastero) formed a clade that was sister to Pseudoseisura, whereas A. urubambensis formed a clade with Schizoeaca and Oreophylax. In a broader genus-level study of the infraorder Furnariides, Moyle et al. (2009) found Asthenes to be paraphyletic with respect to Schizoeaca in that S. helleri (Puna Thistletail) was nested within a group that contained A. humilis (Cabanis) (Streak-throated Canastero), A. urubambensis, and A. baeri (Berlepsch) (Short-billed Canastero). These findings suggested the need for a new phylogenetic classification for taxa currently included in Asthenes and related genera.
As part of a project to reconstruct the phylogenetic relationships of all species in the Furnariidae from DNA sequences (mitochondrial and nuclear), extensive taxon-sampling allowed Derryberry et al. (2010) to determine conclusively that the genus Asthenes consists of two groups that are not sister taxa. One group consists of four species of Asthenes (A. cactorum, A. steinbachi), A. patagonica (Patagonian Canastero), and A. humicola), whereas the second group consists of all remaining species of Asthenes as well as all species sampled from the genus Schizoeaca and Oreophylax moreirae (Itatiaia Spinetail), the sole member of its genus. The type species of Asthenes (A. sordida, currently considered a subspecies of A. pyrrholeuca [Sharp-billed Canastero]) belongs to the large second group. Because no generic name is available for the clade consisting of A. cactorum, A. steinbachi, A. patagonica, and A. humicola (Cory 1919, Cory & Hellmayr 1925, see classification below) Derryberry et al. (2010) described the new genus Pseudasthenes for these four species. After transferring the four species to Pseudasthenes, Asthenes remains paraphyletic because Oreophylax moreirae and all species of Schizoeaca are nested within it. This is the subject of Proposal 434.
Pseudasthenes humicola (Kittlitz)
Pseudasthenes patagonica (d’Orbigny), type of Pseudasthenes
Pseudasthenes steinbachi (Hartert)
Pseudasthenes cactorum (Koepcke)
Figure 1 from Derryberry et al. (2010) --- A simplified majority-rule Bayesian consensus tree of the Furnariidae that highlights the lack of a sister relationship between Pseudasthenes and Asthenes as well as the paraphyly of Asthenes, Schizoeaca, and Oreophylax. Asterisks represent nodes with a posterior probability of 1.0.
Cory, C. B. (1919) A review of Reichenbach's genera Siptornis and Cranioleuca, with descriptions of new allied genera and subgenus. Proceedings of the Biological Society of Washington, 32, 149–160.
Cory, C. B. & Hellmayr, C. E. (1925) Catalogue of birds of the Americas and the adjacent islands, Part IV, Furnariidae-Dendrocolaptidae. Field Museum of Natural History, Zoological Series, 13(3), 1–390.
Derryberry, E., S. Claramunt, K. E. O’Quin, A. Aleixo, R. T. Chesser, J. V. Remsen, Jr., and R. T. Brumfield. 2010. Pseudasthenes, a new genus of ovenbird (Aves: Passeriformes: Furnariidae). Zootaxa 2416:61-68.
Gonzalez, J. & Wink, M. (2008) Phylogenetic position of the monotypic Des Murs' Wiretail (Sylviorthorhynchus desmursii, Aves : Furnariidae) based on mitochondrial and nuclear DNA. Journal of Ornithology, 149, 393–398.
Irestedt, M., FjeldsĆ, J. & Ericson, P. G. P. (2006) Evolution of the ovenbird-woodcreeper assemblage (Aves : Furnariidae) - major shifts in nest architecture and adaptive radiation. Journal of Avian Biology, 37, 260–272.
Moyle, R. G., Chesser, R. T., Brumfield, R. T., Tello, J. G., Marchese, D. J. & Cracraft, J. (2009) Phylogeny and phylogenetic classification of the antbirds, ovenbirds, woodcreepers, and allies (Aves: Passeriformes: Furnariides). Cladistics, 25, 386–405.
Reichenbach, H. G. L. (1853) Handbuch der speciellen Ornithologie (Icon. Syn. Av. No. 10) 146, 168.
Comments from Nores: “YES, porque no queda otra opción. Todos los fundamentos morfológicos y biogeográficos que tenía con este grupo quedan desactualizados por los análisis moleculares. Ningún otro cambio me ha producido una duda tan grande como este caso, no sólo por el nuevo género sino también por las inesperadas relaciones entre las especies. Asthenes baeri y A. dorbignyi, tan parecidos a A. steinbachi resultan tan diferentes, y en cambio se agrupan con Schizoeaca y Oreophylax, un grupo que parecía tan diferente morfológica y biogeográficamente, que además es restringido a los páramos. Como si fuera poco, Pseudoasthenes está relacionado con Pseudoseisura, algo que parecía imposible de ser. Es todo para mi tan inesperado, que no descarto totalmente que haya habido algún error en los análisis moleculares.”
Comments from Stotz: “YES. The genetic data seems clear, although like Manuel, I can’t see much to join Pseudasthenes with Pseudoseisura, there is not real requirement of that. This is a very distinct clade, clear from the rest of the Asthenes mess.”
Comments from Zimmer: “YES. The genetic data seems pretty clear-cut, although I too find the proposed relationship between Pseudoseisura and Pseudasthenes to be both surprising and not particularly helpful biologically, given the clear divergence between the two groups.”
Comments from Jaramillo: “YES. I too find it very surprising. On the other hand, Dusky-tailed, Steinbach’s and Patagonian were always odd ducks, and the relationship between Dusky-tailed and Patagonian seemed relatively clear to me. I don’t know the Cactus, but had assumed it was much more similar to Cordilleran (A. modesta). I guess not. On the other hand, Steinbach’s has always been mentioned as similar to A. dorbignyi, yet in the field it is something altogether different. It is a much more robust, and short-tailed bird and more strikingly colored. Vocally there are some similarities: at least Dusky-tailed, Cactus, and Steinbach’s have two song types. One is a dry trill, and the other is a stuttering trill that speeds up and becomes syncopated towards the end. All recordings I have found of Patagonian are only of a trill type, so maybe it does not have the second song type, or perhaps it is rare. In Dusky-tailed for example the syncopated song is the common one; the trill is rarely heard but it exists. It seems to me that most true Asthenes have a single song type, and in the streaked group it is an accelerating and ascending song for the most part. So, voice appears to tie together Pseudasthenes, and their relatively stocky shape with a short and sometimes rather wide tail, this also is common the group.”
Comments from Pacheco: “YES. Eu considero plenamente aceitável – diante dos resultados encontrados por Derryberry et al. que o novo gźnero Pseudathenes e seu arranjo taxonômico sejam reconhecidos por este Comitź.”