Proposal (424) to South American Classification Committee

Recognize Geocerthia Chesser and Claramunt, 2009

Effect of Proposal: This would add a new genus to our classification, replacing Upucerthia serrana with Geocerthia serrana.

Background: Here’s our Note from current SACC classification, which sums it up well:

“5a. Fjeldså (1992) proposed that Upucerthia serrana and U. andaecola were sister species, based on plumage and voice, and that they formed a monophyletic group with U. ruficaudus and Eremobius phoenicurus, despite the unusual nest of the latter that has led in part to its placement in a monotypic genus. However, Chesser et al. (2007) and Fjeldså et al. (2007) found that serrana is not closely related to andaecola, or to other species currently placed in Upucerthia. See also Notes 7 and 9. Chesser et al. (2009) described a new genus, Geocerthia, for serrana. SACC proposal badly needed.”

New information: Chesser et al. (2009) presented the genetic data that show that Upucerthia, even post-Tarphonomus, remains paraphyletic, and summarized the rationale for a new genus name rather than a more broadly defined Upucerthia (i.e., would require merger of Cinclodes into Upucerthia to retain monophyly). Their tree is as follows:

Recommendation: The genetic data are solid, and the only other option is to merge Cinclodes into Upucerthia; so I recommend a YES.

References:

CHESSER, R. T., S. C. CLARAMUNT, E. DERRYBERRY, AND R. T. BRUMFIELD. 2009. Geocerthia, a new genus of terrestrial ovenbird (Aves: Passeriformes: Furnariidae). Zootaxa 2213: 64-68.

Van Remsen, March 2010

Note (8-10-2010): Because the impending publication of the phylogeny of the Furnariidae will involve wholesale changes in the linear sequence, placement of Geocerthia at this time restricted to moving it from between Upucerthia and Cinclodes and to precede Upucerthia.

Comments from Stiles: “YES. Given solid genetic evidence for the distinctness of serrana, a new generic name seems preferable to lumping of two well-characterized genera.”

Comments from Nores: “YES, es evidente del análisis de Chesser et al. que la especie conocida como Upucerthia serrana no pertenece al género Upucerthia. De todos modos, la creación de nuevos géneros es algo difícil de aceptar pero habrá que acostumbrarse ante la nueva evidencia que presentan los análisis genéticos. Mucho menos aceptable, sería unir esta especie con Cinclodes y Upucerthia.”

Comments from Stotz: “YES. I think the alternative of lumping Cinclodes into Upucerthia is not acceptable. It would create an extremely variable genus, and I think obscure groups of related species.”