Proposal (598) to South American Classification Committee
Recognize newly described Hemitriccus cohnhafti
Effect on SACC: This would add a newly described species to the list.
Background: Zimmer et al. (2013) discovered and described a new species of Hemitriccus, H. cohnhafti, from the Brazil-Bolivia border in the southeastern part of the state of Acre, based on two adult male and one adult female specimens deposited in the Museu Paraense Emilio Goeldi (MPEG), Belém, Brazil, and on audio recordings of at least 6 different individuals. As far as is known, the species is restricted to the type locality, which is on the Brazil-Bolivia border (ca. 500 m from the Acre River) and only about 10 km from the Brazil-Peru border. Thus, it is expected that the new species will eventually be found in the Departments of Pando in Bolivia and Madre de Dios in Peru since the Acre River probably does not represent a barrier to the dispersal (it is only about 100 m wide) of H. cohnhafti.
DNA sequence data from the mitochondrial gene cytochrome b (1026 base pairs) obtained for 10 individuals of H. cohnhafti, H. spodiops, H. zosterops and H. minor confirmed the genetic differentiation of H. cohnhafti and its placement with high statistical support as sister to H. spodiops (Fig. 2 in Zimmer et al. 2013). These two species, in turn, were found to be sister to H. minor pallens, confirming earlier analyses carried out without samples of H. cohnhafti (Cohn-Haft 2000, Sardelli 2005). In plumage and morphology, the species is distinguished from all congeners except H. minor and H. spodiops by its large, round and exposed nostrils, and by the arched culmen. It is further distinguished from all known populations of H. minor by the distinctive buff-colored feathering of the loral and supraloral region, and the more distinctive wing bars. It is most similar to but diagnosably different from the H. spodiops in having noticeably shorter crown feathers (H. spodiops has a more crested appearance); the ground-color of the crown is essentially concolor with the darker and duller olive back (versus contrastingly brownish compared to the somewhat brighter green mantle in H. spodiops). It is further distinguished in having two distinct, somewhat bronzy wing bars (indistinct in H. spodiops), a pale panel, formed by bronzy edges to the secondaries (the secondaries edged yellowish-green in H. spodiops), and a buffy coloration confined to the loral and supraloral regions contrasting with the rest of the face. The two species also differ diagnostically in vocal characters: duration, number of notes, peak frequency pattern, and multiple calls that appear to be unique to one species or the other (Fig. 1 in Zimmer et al. 2013).
Analysis/Recommendation: The fact that the phylogenies recovered H. spodiops and H. cohnhafti as reciprocally monophyletic taxa with strong statistical support (Fig. 2 in Zimmer et al. 2013), along with their morphological and vocal differentiation, supports their recognition as valid species-level taxa (De Queiroz 2007). We therefore strongly recommend a YES vote on this proposal.
Cohn-Haft, M. (2000). A case study of Amazonian biogeography: vocal and DNA-sequence variation in Hemitriccus flycatchers. PhD. Dissertation, Department of Biological Sciences, Louisiana State University, Baton Rouge, LA.
De Queiroz, K. (2007). Species concepts and species delimitation. Systematic Biology 56 (6): 879-886.
Sardelli, C. H. (2005). Variação geográfica e genética de Hemitriccus minor (Aves- Tyrannidae) na Bacia do Madeira, AM/Brasil. MSc Thesis, lnstituto Nacional de Pesquisas da Amazonia, Manaus, Brazil.
Zimmer, K. J.; Whittaker, A.; Sardelli, C.; Guilherme, and Aleixo, A. (2013) A new species of Hemitriccus tody-tyrant from the state of Acre, Brazil. In: J. del Hoyo, A. Elliott e D. Christie. (Org.). Handbook of the Birds of the World, Special Volume: New Species and Global Index. 1ed.Barcelona: Lynx Edicions, 292-296.
Leonardo S. Miranda and Alexandre Aleixo, October 2013
Note from Remsen: Zimmer et al. (2013) proposed the English name “Acre Tody-Tyrant”, which will be the default name for the species if the proposal passes.
Comments from Stiles: “YES. Genetic, vocal and morphological data seem consistent with recognizing this species.”
Comments from Zimmer: “YES, based on the vocal, morphological and genetic data presented in Zimmer et al (2013) and summarized in the Proposal.”
Comments from Pacheco: “YES. As diferenças morfológica e vocal corroboram a validade deste táxon recuperada a partir dos dados moleculares.”
Comments from Robbins: “YES, all data support recognizing Hemitriccus cohnhafti as a species.”
Comments from Jaramillo: “YES, morphology, voice and genetics all confirm a new species here.”