Proposal (#29) to South American Classification Committee
Remove Euphonia and Chlorophonia from Incertae Sedis and place as subfamily Euphoniinae in Fringillidae
Effect on South American CL: We currently treat the genera Euphonia and Chlorophonia as Incertae Sedis within the 9-primaried oscines. This proposal would move them to Fringillidae, as a subfamily (and therefore also force recognition of subfamily Carduelinae for the fringillids in South America).
Background: Although Euphonia and Chlorophonia have always been placed in Thraupidae, several aspects of their biology have marked them as "weird." The complex, melodious songs of some species have been noted as superficially "goldfinch-like" and unlike that of most tanagers The presence of pronounced vocal copying in E. violacea, E. laniirostris, and E. pectoralis (Snow 1974, Morton 1976, Remsen 1976, Sick 1997) is unlike any tanager but reminiscent of several fringillids (e.g., Mundinger 1970, Remsen et al. 1982, Taylor 1979). The domed nest with side entrance is unlike that of any typical tanager (Isler and Isler 1987). The vagility of some (e.g., E. chlorotica, C. cyanea, C. flavirostris) seems unusual for tanagers but typical of fringillids, as do reports of large single-species flocks in at least one species, C. flavirostris. The near-vegetarian diet recalls that of many fringillids, and their stomach "structure" is bizarre. They feed their young by regurgitation, unlike (?) tanagers but like many fringillids. None of these features, however, has been accorded any phylogenetic significance.
New data: Four labs have independently shown that Euphonia does not belong in Thraupidae but clusters with Fringillidae (Burns 1997, Burns et al. 2002, Klicka et al. 2000, Sato et al. 2001, and Yuri and Mindell 2002). My only hesitation is that these results are based mostly on one gene, cytochrome b. Although Sibley & Ahlquist (1990) retained Euphonia within their Thraupini, that branch was the deepest in the group, which also included Piranga, Habia, Coereba, and Sicalis.
Recommendation: I recommend a YES on this one. The AOU Checklist Committee has unanimously approved a similar proposal by Jim Rising, and created a subfamily taxon, Euphoniinae, for these two genera within Fringillidae. Although I would feel more comfortable if some sequence data came from a nuclear gene, I see no reason other than historical momentum to keep these two genera in Thraupidae. The additional phenotypic, albeit anecdotal, data is also consistent with a fringillid connection.
BURNS, K. J. 1997. Molecular systematics of tanagers (Thraupinae): Evolution and biogeography of a diverse radiation of Neotropical birds. Molecular Phylogenetics and Evolution 8:334-348.
BURNS, K. J., S. J. HACKETT, & N. K. KLEIN. 2002. Phylogenetic relationships and morphological diversity in Darwin's finches and their relatives. Evolution 56: 1240-1252.
ISLER, M., AND P. ISLER. 1987. The tanagers, natural history, distribution, and identification. Smithsonian Institution, Washington, D.C.
KLICKA, J, K. P. JOHNSON, & S. M. LANYON. 2000. New World nine-primaried oscine relationships: constructing a mitochondrial DNA framework. Auk 117: 321-326.
MORTON, E. S. 1976. Vocal mimicry in the Thick-billed Euphonia. Wilson Bull. 88: 485-487.
MUNDINDER, P. C. 1970. Vocal imitation and individual recognition of finch calls. Science 168: 480-482.
REMSEN, J. V., JR., K. GARRETT, & R. ERICKSON. 1982. Vocal copying in Lawrence's and Lesser goldfinches. West. Birds 13: 29-33.
SATO, A., H. TICHY, C. O'HUIGIN, P. R. GRANT, B. R. GRANT, & J. KLEIN. 2001. On the origin of Darwin's finches. Mol. Biol. Evol. 18: 299-311.
SIBLEY, C. G., AND J. E. AHLQUIST. 1990. Phylogeny and classification of birds. Yale Univ. Press, New Haven, Connecticut.
SICK, H. 1997. Ornitologia Brasileira. Ed. Nova Fronteira, Rio de Janeiro.
TAYLOR, P. 1979. Interspecific vocal mimicry by Pine Grosbeaks. Can. Field Nat. 93: 436-437.
YURI, T., & D. P. MINDELL. 2002. Molecular phylogenetic analysis of Fringillidae, "New World nine-primaried oscines" (Aves: Passeriformes). Molecular Phylogenetics & Evolution 23: 229-243.
Van Remsen, 5 June 2003
Comments from Zimmer: "I vote "YES" on this one. The preponderance of vocal, ecological, morphological and molecular data all suggest this otherwise."
Comments from Schulenberg: "My
vote: "Yes". That said, I don't see that Burns 1997 or Burns et al.
2002 include any fringillids among their outgroups. So, these two papers
support the idea that Euphonia and Chlorophonia are not tanagers (whatever a tanager is), but do not directly address the current proposal. And, therefore, we are down to three (not four) laboratories that report this result, not that this matters much.
"Otherwise, I also note that these studies generally compare a euphonia to a cardueline (although a different species of Euphonia in each case), so our sampling isn't very deep here. (Yuri and Mindell do a little better in this regard.) Klicka et al. were cautious in suggesting that their results, for example, indicate that "Euphonia (and by association Chlorophonia) represents either a derived cardueline form or a basal, previously unrecognized radiation within the nine-primaried oscine clade." So, I can approve the proposal based on current knowledge. But I also wouldn't be surprised if down the line, after the relationships of Euphonia and Chlorophonia become the subject of an investigation (and not just a side issue to some other question), we are asked to vote on recognizing a family Euphonidae, or something along those lines. Time will tell."
Comments from Stotz: "Tom's suggestion that we might eventually have a separate Euphoniidae someday is interesting, and could be true. However, Yuri and Mindell did have stronger taxon sampling relating to this question (six Fringillid genera) and Euphonia did not end up basal in this group. Since that paper is based on just mitochondrial DNA, it certainly is not the last word, but it does suggest that Euphonia and Chlorophonia belong within Fringillidae proper. Another problem is that based on Yuri and Mindell, Euphonia and Chlorophonia could cluster within Fringillidae, in which case we'd have to do away with Euphoniinae. Since the SACC list does not include subfamilies, I guess we don't need to worry about this. Given that Euphonia clusters with Fringilla in Yuri and Mindell, I suggest that Euphonia and Chlorophonia be placed at the start of the of Carduelinae in their lists."
Comments from Stiles: "YES (the evidence now seems solid enough to justify this change)>"