Proposal (131) to South American Classification Committee
Change English name of Microcerculus marginatus from "Nightingale Wren" to "Southern Nightingale-Wren"
This will be the second-shortest, second-flimsiest proposal I've written so far.
Microcerculus marginatus was known "forever" as "Nightingale Wren" until that troublemaker Gary Stiles showed that there were two parapatric species-level taxa in Costa Rica.
For better or worse, the AOU solution to the split was to elevate the two "groups" of the 1983 Checklist to species and carry the English names with them, namely "Nightingale Wren" for the northern philomela group, and "Scaly-breasted Wren" for southern marginatus group (including all of South America).
Ridgely & Tudor (1989) chose to go with "Northern Nightingale-Wren" and "Southern Nightingale-Wren" for the two. In some ways this is better (albeit insipid) because to use the former name "Nightingale Wren" for one of the daughter species, especially the one with the junior name, can cause confusion. Ridgely & Tudor (1989) didn't mention that -- what they did say was:
"[The AOU] ... suggested calling M. marginatus the Scaly-breasted Wren, an unfortunate choice, as birds from most of its range do not have scaly breasts."
I beg to differ with the latter statement. Our large series of marginatus from Central America to Bolivia and Brazil shows lots of individual (age?) and some pronounced geographic variation, but "scales" are present on the breast, or certainly their sides, in a high % of the specimens. Even the cleanest-breasted birds have "scales" at the margins of the official breast in the flanks and upper belly. "Scaly-breasted" isn't a great name for these birds, but the statement above is clearly in need of revision.
The lurking problem that most of you know about is that within the species we currently treat as one, it is likely that two or more additional species-level taxa exist. For example, the trans-Andean luscinia group differs more strongly in plumage from cis-Andean birds than it does from parapatric philomela. Within Amazonia, song differences are dramatic and screaming out for a formal analysis. Therefore, it's likely we'll be facing further fragmentation of marginatus. The relevance to the English name situation is that we should be thinking ahead, namely would you rather have additional "Something Nightingale-Wren" compound names or come up with additional "single names". The name "Whistler Wren" is already available for the luscinia group, which I find personally more appealing than "Whistler Nightingale-Wren" or something like that.
Recommendation: I vote NO on this because of a personal preference (echoed, by the way, by many or most birders as well as ornithologists that I know) for simpler, non-compound names.
Van Remsen, August 2004
Comments from Stiles: "NO. I am not enamored of "Scaly-breasted Wren" (in cis-Andean forms, only the juveniles have truly "scaly" breasts), but I like three-part names even less (ESPECIALLY when "disguised" by hyphens, as in "barn-owl", "slaty-antshrike" - or "nightingale-wren"). Since the group is ripe for a good study with some splitting likely, let's stay with "scaly-breasted" until somebody does it, then sort out the English names!"
Comments from Robbins: "NO, there is no need to start changing names until this complex receives a thorough analysis and species limits are defined."
Comments from Nores: "YES, estoy de acuerdo. Por un lado, me parece bien conservar el nombre nightingale para las dos especies y además el detalle del pecho no es tan importante como para denominar comúnmente a la especie. Pienso que los nombres muy particulares deberían ser mantenidos cuando se separa una especie en dos especies. Supongamos que se comprueba que las poblaciones europeas de Anas platyrhynchos son diferentes específicamente de las americanas. Yo no estaría de acuerdo en decirle Mallard a uno de ellos y Green-headed Duck al otro, por ejemplo. Yo les pondría American Mallard y European Mallard."
Comments from Zimmer: "This is another one (see Proposal #130) where I vote "NO" with extreme reluctance. I have real problems with calling the birds in Brazil "Scaly-breasted Wren" when the adults are so white-breasted. The best name for the group as a whole (excluding the northern Philomela group, for which we use "Nightingale Wren") is Gary's "Whistling Wren," which he applied specifically to the luscinia group. I would be tempted to push for that name being applied to what we currently call "Scaly-breasted Wren", because it would be a much more accurate name when the entire group is taken into account. However, assuming that someone will eventually split this marginatus complex up into multiple species (as is suggested by both morphological and vocal distinctions), it would be nice to be able to retain the name "Whistling Wren" for luscinia. I share the reluctance of others to use the longer, hyphenated names if a better alternative can be found. That brings us back to Scaly-breasted Wren, which I dislike intensely, given that it is downright misleading over a large part of the range (You may be able to discern scaling at the margins of the breast on specimens, but try explaining the name to a group of birders looking at what appears to be a clean white breast glowing out of the gloom of the forest understory!). I would like to just punt on this one ... "
Comments from Stotz: " NO. I actually don't know what to do here. I have to say that my South American perspective has me a bit irritated that Nightingale Wren has been appropriated for the Central American form. To me the birds I hear in Amazonia will remain Nightingale Wrens. Having said that, I think it would be a mistake to go change this English name when we all know that the taxonomic situation is not stable, and it would essentially argue for changing the extralimital Nightingale Wren to Northern Nightingale-Wren (or something). Marginatus will certainly be split up. When it is, I hope that the author provides us with good English names."
Comments from Pacheco: "[NO] Acompanho o voto de Remsen, pela simples razão por ele apresentada. Quando uma revisão do complexo estiver disponível, novos nomes em Inglês serão necessários."
Comments from Jaramillo: "NO. Retain Scaly-breasted Wren, these hyphenated names are some of my least favorite names of all!"