Home About Committees North American Classification Committee Current & Prior Proposals 2019 Proposals Comments 2019-C

Comments 2019-C

2019-C-1: (a) Transfer Blue-black Grosbeak Cyanocompsa cyanoides to Cyanoloxia. (b) Transfer Blue Bunting Cyanocompsa parellina to Passerina

(a) YES. Makes sense given the molecular data and to be consistent with the SACC. (b) YES. Seems a reasonable treatment and especially given the alternative of merging Amaurospiza, Cyanocompsa, and Cyanoloxia into Passerina.

(a) YES, for all the reasons outlined in SACC Proposal 726 and comments therein. (b) YES, following recommendations of Bryson et al. (2014) and to avoid retaining monotypic Cyanocompsa, especially given that a reasonable alternative will be to merge all three genera plus Amaurospiza into Passerina.

(a) YES. (b) NO. 2 without comment.

(a) YES. (b) NO due to varying generic limits.

(a) YES. (b) NO. I’m uneasy about moving Cyanocompsa parellina to Passerina without additional genetic support. This sampling should include the allopatric Pacific slope of west and south Mexican indigotica which has a very different plumage for the females and I believe different vocalizations (including contact notes). It may represent a different species.

(a) YES. Transfer cyanoides to Cyanoloxia (brissonii does not occur in our area). (b) NO. Retain parellina (the type species) in Cyanocompsa. This choice involves the least amount of changes, and retains a monophyletic parellina, which may be appropriate, given that the mtDNA data set is not particularly strong for the parellina in Passerina node. 

(a) YES. This is clearly dictated by the phylogeny. (b) NO. As it is basal to Passerina, I think it should be retained in a monotypic Cyanocompsa, of which it is the type species, at least until further analyses provide stronger support for inclusion within Passerina.

(a) YES. This clearly has to be done to match up with the phylogeny in Bryson et al. (b) NO. I have gone back and forth on this. In some ways it is cleaner to put parellina in Passerina with all of the other buntings. However, it does stand out in the tree relative to everything else in Passerina, and I think emphasizing that it is not clustering with the other  blue buntings (and Grosbeak) is probably worth doing. I would not favor the mentioned but not formally proposed idea of lumping all of these genera into the single genus Passerina. I see there being well-defined clades that make biogeographic and ecological sense. Putting them all together would obscure information that is visible with the recognition of multiple genera.

2019-C-2: Split extralimital Amazonian Grosbeak Cyanocompsa (Cyanoloxia) rothschildii from C. cyanoides (Blue-black Grosbeak)

YES. 2 without comment.

YES, for all the reasons outlined in SACC Proposal 736 and comments therein. For the English name Amazonian Grosbeak, see SACC Proposal 789.

YES. Concordant data in morphology and genetics – more evidence that they are two species (under several definitiations) than they are a single species.

YES. I support this split based on the congruence of phenotypic, molecular, and vocal differences (although there is overlap in song traits and it would be nice to see more formal playback experiments), and for consistency with the SACC since rothschildii is extralimital to the NACC area.

YES. I remain convinced that this is the best treatment of this complex, especially given the vocal differences between rothschildii and cyanoides. I see no reason not to adopt the English name Amazonian Grosbeak for rochshildii and maintain Blue-black Grosbeak for cyanoides.

YES. Phenotypically this makes sense, with the males of rothschildii having noticeably brighter blue and larger forehead and malar region patches lacking or subdued in the other taxa. Females appear identical in color. Vocally they apparently differ at least typically, and the deep divergence is strongly suggestive of long isolation.

YES. I would be a bit more picky if this taxon were in our area, but given that rothschildii is only in South America, and that the SACC chose to split, it would take a preponderance of evidence to convince me to vote against it. Actually, most evidence favors a split, even though some of the evidence is kind of weak (only mtDNA, no playbacks experiments, etc.).

YES, but barely. None of these factors alone is convincing to me, but all together (including SACC decision) leads me to approve.

2019-C-3: Transfer subspecies cabanidis from Lesser Violetear Colibri cyanotus to Mexican Violetear C. thalassinus, and delete Lesser Violetear from the North American list

NO. 1 without comment.

NO. This puts too much weight on mtDNA for species limits.

NO. I’m more inclined to eventually favor the suggested three species treatment.

NO, but weakly. The genetic results are not particularly strong to remove cabanidis from cyanotus (0.8 posteriori value, and only mt DNA genes). The plumage results need more work. What about size? Isn’t cyanotus (+ cabanidis?) supposed to be smaller?

NO. I am not certain what the appropriate treatment of this complex is, but I think the molecular data is insufficient at present to continue to fiddle with our treatment.

NO. Support for the node uniting cabanidis and thalassinus is not particularly strong (0.8). Looking at the tree structure alone, I think the topology supports three species: cyanotis/crissalis, cabanidis, and thalassinus. However, I would be wary of making changes just based on the tree structure; additional data and analyses (of morphology and other molecular markers) are needed.

NO. While the data are suggestive, they are based solely on two mtDNA genes with only moderate support for the sister relationship between cabanidis and thalassinus, and on qualitative assessments of plumage coloration. More study is necessary before making this change.

NO. Quintero and Perktaş (2018) is based on mtDNA gene trees. Further (not mentioned in the proposal) is that the support for the cabanidis–thalassinus sister relationship is substandard. This is insufficient to overturn a traditional, albeit revived, classification. A three-species classification looks like the best solution, given the tree topology, but additional analyses are required. (Of tangential interest is that Quintero and Perktaş (2018) did not cite Remsen et al. [2015], the only other ever paper published specifically on the phylogeny and classification of Colibri and relatives.)

NO. Based on the large USNM collection of all these taxa except crissalis (evidently an indistinct race), cabanidis looks to be more similar phenotypically to cyanotus than to thalassinus on ventral coloration, but usually (at least in adult males) with a distinct blue-green center of upper belly-lower breast, vs. distinct dark purple patch bordered by blue-green in thalassinus. Thus I don’t really see cabanidis as being phenotypically intermediate between cyanotus and thalassinus, or at least it is much closer in ventral coloration to the former, so I don’t think cabanidis should be lumped with thalassinus. If the phylogeny were better supported I would go for a 3-species treatment, but as it is I agree that we should wait for a better-supported phylogeny.

2019-C-4: Transfer Gray-capped Cuckoo Coccyzus lansbergi to the Main List

YES. 6 without comment.

YES. Diagnostic photographs of this quite distinctive cuckoo.

YES. Archived, diagnostic photos support transfer to Main List.

YES. Good photos of this species from the region covered by the North American committee.

2019-C-5: Transfer Dwarf Cuckoo Coccycua pumila to the Main List

YES. 6 without comment.

YES. Diagnostic photographs of this quite distinctive cuckoo.

YES. Published and archived diagnostic photos support transfer to Main List.

YES. Good photos of this species from the region covered by the North American committee.

2019-C-6: Revise generic limits in the Thraupidae: (a) Tranfer Tiaris bicolor to Melanospiza. (b) Transfer Tiaris canorus to Phonipara. (c) Transfer Tangara guttata to resurrected genus Ixothraupis. (d) Transfer Tangara palmeri and T. cabanisi to new genus Poecilostreptus. (e) Transfer Tangara cucullata and T. larvata to new genus Stilpnia

YES to all. 4 without comment.

YES. I vote for all of the recommended changes for reasons given in the proposal and for consistency with the SACC.

YES to all of these changes. This molecular work is clarifying relationships that to this point have mostly the support of tradition behind them. SACC proposal 730 provides much more detail and argument supporting these changes than does the current proposal.

YES. These changes look necessary. The first two are not surprising, considering the mess that is the taxonomy of grassquits and the Caribbean radiation of seedeater-like species. If we are to maintain the distinct and defined genus Thraupis, then the latter three sub-proposals are necessary. Note that cabansi was not included in the genetic analyses of Burns et al. 2014, but is phenotypically similar enough to palmeri to consider them sisters. 

(a) YES, for all the reasons mentioned in SACC proposal 730.04, which passed in July 2018 (see for photographs of Tiaris bicolor and Melanospiza to see how similar they are). (b) YES. Required by the new phylogenetic data. (c) YES, for all the reasons outlined in SACC proposal 730.19, which passed almost 2 years ago (see for photographs of the members of Ixothraupis to illustrate their plumage similarities). (d) YES, for all the reasons outlined in SACC proposal 730.20, which passed in July 2018. (e) YES, for all the reasons outlined in SACC proposal 730.20, which passed in July 2018.

(a) YES. (b) NO. I don’t agree that resurrecting a montypic genus because a species’ relationships remain to be resolved is a good way to solve this situation. This is why we have incertae sedis formally defined by ICZN. (c) YES. (d) YES. (e) YES.

2019-C-7: Split Yucatan Gnatcatcher Polioptila albiventris from White-lored Gnatcatcher P. albiloris

YES. 2 without comment (Option 3).

YES. Option 2. This taxon is not an albiloris, and let’s not consider it a monotypic species yet. For now, let’s place albiventris as a subspecies of plumbea. The most recent published evidence (Smith et al. 2018) does not provide sufficient basis for full evaluation as a biological species. The authors themselves stated: “All of the statistically inferred taxa should be considered fundamental evolutionary units for conservation decisions and evolutionary studies. For most, determining whether or not they are biological species will require additional work in genetic sampling, study of song, morphology, behavior, and putative hybrid zones.”

YES. Option 2 for now. The molecular data clearly show that albiventris is nested within the plumbea complex and is distinct from albiloris. The vocal information further supports a split from albiloris. However, without considering the plumbea complex (and especially the bilineata group) at the same time, some questions remain. I would have liked to see some sonograms in the proposal (minimally), and more quantitative analysis of the vocal differences (especially comparing albiventris and the bilineata group of plumbea). Also, the proposal says that “The geographic range of albiventris is, however, encircled by (but probably allopatric from) that of the bilineata group.” Are they truly allopatric, and do we know if these contact anywhere? If they contact, what happens in the contact zone? How do they respond to the vocal differences? I don’t like to leave albiventris in albiloris, but I don’t feel like we have enough information to make a decision on whether albiventris should be treated as a separate species. For now the best option is probably to treat it as a subspecies of plumbea, although I’m not super happy with that either.

YES. Option 3. I would adopt treating albiventris as a distinct species. P. albiventris needs to be split from albiloris. As far as considering albiventris as a subspecies of the bilineata group of plumbea, I think that is a step in the wrong direction, given that plumbea certainly needs to be split, and albiventris differs in plumage, ecological and vocal characters from plumbea.

YES. Option 3. Yucatán Gnatcatcher is appropriate for the English name. Species limits within Polioptila are open to further investigation, including within Blue-gray Gnatcatcher (Polioptila caerulea) where nominate caerulea and western obscura differ visually and vocally (song, and slightly on contact calls) as well as habitat, and there are other isolated populations (e.g. Bahamas and Cozumel) that should be looked at too.

YES. Option 3 based on vocalization and genetic differences.

YES, tentatively Option 3. This is a real tough one. I agree that albiventris does not belong with albilora, and should be removed. The question as to whether to merge it into the bilineata group of plumbeiceps or to raise it to species level is more difficult.  Given that several taxa within the bilineata group likely deserve species status, despite shallow genetic divergence, and the vocal and morphological differences, I agree that albiventris should be given species status.

YES. Option 3. As noted by Smith et al. (2018) and the proposal, genetic and vocal data show that albiventris cannot be retained in albiloris. Thus, the only question is whether to treat albiventris as a subspecies in the bilineata group or as a separate species. Although I would prefer that the excellent rationale for treatment as a separate species be published, I think we can use Davis (1972) and the recommendation of Smith et al. (2018) as sufficient justification for treatment of albiventris as a separate species. I also see no reason not to go with Davis’ English name, Yucatan Gnatcatcher.

2019-C-8: Transfer Maroon-chested Ground-Dove Claravis mondetoura to new genus Paraclaravis

YES. 2 without comment.

YES. This does seem fairly clear.

YES. The phylogenetic data support this change, although the basal relationships are not well-supported. This is a better alternative than merging multiple genera.

YES. Clear outcome of the phylogenetic work.

YES, but with hesitation. The nodes preventing monophyly of traditional Claravis are two nodes in the 70’s in the mtDNA tree and one node with 86% bootstrap support in the fibrinogen tree. I would be more comfortable with this change if we had higher support for those nodes. It might be better to wait.

YES. Genetic results clearly indicate this is necessary. Both species of Paraclaravis are also forest species tied to fruiting bamboo.

YES. This is a better alternative than creating an overly broad genus.

YES. New phylogenetic data require treating this (and geoffroyi) in a new genus, unless we merge Claravis, Uropelia, Columbina, and Metriopelia to produce an exceptionally heterogeneous group.

2019-C-9: Treat Orange-bellied Trogon Trogon aurantiiventris as conspecific with Collared Trogon T. collaris

YES. 2 without comment.

YES. All the evidence suggests this is a color morph.

YES, based on the phylogeny and information provided on vocalizations and likely hybridization.

YES. The molecular data combined with the phenotypic similarity and supposed lack of vocal differences (not sure what that is based on, no citation given in the proposal) suggests that a subspecific treatment is better – although I’m bothered by the lack of information from the area of supposed sympatry.

YES. Ordinarily, I do not like putting too much emphasis on mtDNA and species limits, but here the morphological evidence is compelling as well.

YES. Especially given similarities in voice, which are usually diagnostic with sympatric species of trogons. Given that the belly colors are produced by cartonoids, the differences between the two taxa may be purely from diet, and have no underlying genetic differences. 

YES, but somewhat reluctantly. This situation is “data-deficient,” but the bulk of the weak evidence we have for a decision places burden-of-proof on treating aurantiiventris as a separate species from T. collaris.

YES. I have mixed feelings on this, mostly because of the apparent elevational difference between the two taxa. However, the variability in the color of the underparts of different populations of aurantiiventris  suggest that there might be intergradation occurring, and the fact that there do not appear to be vocal differences make it difficult to maintain these as separate species.

2019-C-10: Split extralimital Monteiroi’s Storm-Petrel Oceanodroma monteiroi from Band-rumped Storm-Petrel O. castro

YES. 2 without comment.

YES. There is a lot of evidence to suggest that these two storm-petrels are reproductively isolated (genetics, morphology, nesting phenology, feeding ecology, voice, molt, and lack of intermixing).

YES. Evidence seems overwhelming!

YES. This group is all a huge can of worms, but everything says that there are two species breeding on those islands in the Azores. Who knows what is going on in the non-breeding season.

YES. The evidence for the existence of two species in the Azores is extraordinarily thorough and convincing. The only possible reason I could see not to recognize monteiroi at this time is the still-unresolved nature of the species complex elsewhere. However, it seems obvious what the situation is in the Azores, and the impact on our region of recognizing the extralimital monteiroi, which is widely recognized elsewhere, is marginal and so not strongly confounded by the broader problem. (An exceptionally well-prepared proposal, by the way.)

YES. The evidence looks clear.

YES. This is well-supported on the BSC basis, but no doubt there are more cryptic species within this widely occurring species with warm and cold water breeders, a species that was widely before and even more widely now treated as monotypic.

YES. Collectively the evidence seems definitive.

2019-C-11: Transfer subspecies approximans from Thick-billed Vireo Vireo crassirostris to Mangrove Vireo V. pallens

YES. 3 without comment.

YES, based on the vocal evidence provided.

YES. There are clear vocal differences between approximans and crassirostris that align it more with pallens. There are also phenotypic similarities between approximans and pallens. It would be great to get some genetic data, but this seems like a better treatment for now and it is consistent with other current treatments.

YES. This is fixing a historical misplacement of this taxon in crassirostris. Vocally it clearly goes with pallens. I could imagine that we might eventually want to split it off entirely, but I don’t think we have the necessary info yet. This is an obvious improvement on the current treatment.

YES. The songs of crassirostris and pallens are strikingly different and much of this has to be genetically based. The songs (calls?) of approximans are quite similar to pallens, and utterly different from crassirostris. In the absence of an in-depth analysis (genetic, vocalizations, morphology) I think the best course is to put approximans with pallens.

YES. Not a Thick-billed Vireo, so action needed. Hopefully we are putting it with the right species as opposed to recognizing it as an endemic island species.

YES. The three USNM specimens (including the type) of approximans are quite similar to the yellow-bellied Caribbean races V. p. ochraceus and V. p. semiflavus except in having a larger, longer bill, perhaps slightly larger size, and slightly paler upperparts. They are more similar to V. pallens in face pattern, owing to a weakly dark eyestripe in front of eye and rather narrow duller yellow lores, vs. usually black eyestripe in front of eye with strong broad yellow lores in crassirostris. I would think that face pattern is more likely to be indicative of relationships than bill size, especially since small island races often have large bills. Given that the voice of approximans is so similar to that of pallens, this does seem to be a case of overturning an earlier mistake. As for the suggestion that approximans might be a separate species, I don’t see anything obvious from the specimens to support that possibility.