Proposal (586) to South American Classification Committee
Recognize newly described Herpsilochmus praedictus
Effect on South American CL: This proposal would add a newly described species to the list.
Background: During survey work in the vicinity of Humaitá, Amazonas, Brazil, in July 1999, Mario Cohn-Haft encountered Herpsilochmus antwrens in mixed-species canopy flocks on the left side of the Rio Madeira. Although very similar-looking to other white-bellied Amazonian species in the genus, such as H. dorsimaculatus from the Rio Negro basin, this population had distinctive vocalizations. A preliminary comparison between recordings of these birds and other Herpsilochmus species (Whitney et al. 2000) suggested that this population represented an undescribed vocal type.
New information: Cohn-Haft and Bravo (2013) presented information on plumage, vocalizations, phylogenetic relationships, and geographic distribution of this distinctive population. This population has now been confirmed primarily in various localities between the Purús and the Madeira rivers, but a couple of localities W of the Purús are also known for the species. Thus, its true western and southern limits remain uncertain.
Maximum-likelihood and Bayesian analyses of mtDNA showed that this population belongs in an Amazonian clade, with a population found E of the Rio Madeira (Herpsilochmus stotzi; Whitney et al. 2013), from which it is ~4% divergent. This Amazonian clade is ~6% divergent from a clade containing H. atricapillus, H. pileatus, as well as the Andean representatives H. motacilloides and H. parkeri. Comparison of 9 specimens and 25 recordings of H. stotzi showed that it is diagnosed by voice and plumage (especially that of females) from all other members in the H. pileatus complex.
Therefore, Cohn-Haft and Bravo concluded that this population deserved species-level status and described it as a new species, which they named Herpsilochmus praedictus. The name refers to the fact that the existence of this species was predicted before it was actually found and recognized.
Recommendation: Given the results of Cohn-Haft and Bravo, there is no question that H. praedictus is not only a distinctive population, but also a valid species-level taxon from which no name was previously available. Therefore, I recommend a YES vote to recognize H. praedictus as a valid species. The English name Predicted Antwren seems appropriate given its scientific name.
Cohn-Haft, M. and G. A. Bravo (2013). A new species of Herpsilochmus antwren from west of the Rio Madeira in Amazonian Brazil. Pp. 272–276 in: del Hoyo, J., A. Elliott, J. Sargatal, and D. A. Christie (eds.) (2013). Handbook of the Birds of the World. Special Volume: New Species and Global Index. Lynx Edicions, Barcelona.
Whitney, B. M., J. F. Pacheco, D. R. C. Buzzetti, and R. Parrini (2000). Systematic revision and biogeography of the Herpsilochmus pileatus complex, with description of a new species from northeastern Brazil. Auk 117: 869–891.
Whitney, B. M., M. Cohn-Haft, G. A. Bravo, F. Schunck, and L. F. Silveira (2013). A new species of Herpsilochmus antwren from the Aripuanč-Machado interfluvium in central Amazonian Brazil. Pp. 277–281 in: del Hoyo, J., A. Elliott, J. Sargatal, and D. A. Christie (eds.) (2013). Handbook of the Birds of the World. Special Volume: New Species and Global Index. Lynx Edicions, Barcelona.
Gustavo A. Bravo, September 2013
Comments from Stiles: “YES, in line with the previous proposal. The English name does not inspire me, and given the nature of the riverine barriers involved plus the rather weak plumage differentiation, I suspect that a more geographical name would be more useful, especially to field workers – perhaps Purus Antwren, since this species occurs on both sides of this river.”
Comments from Pacheco: “YES. Sem qualquer objećčo. A diagnosticabilidade do táxon (morfológica / genética) foi bem demonstrada pelos autores. “
Comments from Zimmer: “YES. As with H. stotzi, species status for the previously unknown population of Herpsilochmus from west of the Madeira is strongly supported by both vocal and genetic data, and only weakly supported by plumage differences. Both of the newly described Herpsilochmus are textbook examples of the biogeographic significance of river barriers in Amazonia. I too am not wild about the suggested English name – it sounds a little too strained. I like Gary’s suggestion of Purus Antwren, which not only imparts some information about its distribution, but also highlights the biogeographic importance of the south bank tributaries of the Amazon.”
Comments from Jaramillo: “YES. As in 585, this seems like a solid new species. I really like the English name, it is distinctive and memorable…and we need that in antbirds!”
Comments from Robbins: “YES, for the same rationale that was given for recognizing H. stotzi.”
Comments from Pérez-Emán: “YES, for the same reasons indicated in the previous proposal. Increasing knowledge about the systematics of this genus is a great contribution for understanding biogeography of Amazonian birds.”
Comments from Remsen: “YES. All data indicate species rank for praedictus. I agree with Gary and Kevin on the English name issue.”