Proposal (1078) to South American Classification Committee

Change the English name of Camptostoma obsoletum (sensu stricto)

The English names for the various species resulting in the split of Camptostoma obsoletum (sensu lato) were decided in proposal 1062, some after a lot of back-and-forth discussion and multiple voting rounds. The AviList English Names Committee (ENC) has since also voted on names for these species, and for five of the six they unanimously accepted the names decided by SACC. However, Camptostoma obsoletum (sensu stricto) has continued to cause problems. For that species, the AviList ENC voted 6-1 to not use the name Southern Beardless-Tyrannulet, and to go with Austral Beardless-Tyrannulet. However, as advocated by several voters on proposal 1062, that name is (depending on who you ask) somewhere between less than ideal to downright horrible.

Despite the guideline that for most split species the former common name should be retired, it has been pointed out that this is merely a guideline. Others would point out that the risks of retaining the name are especially egregious when the English and scientific name would stay the same, or when a split is not a simple two-way split but a multi-way division of a widespread species. There are additional reasons that this particular case could be considered among the worst possible to make that exception. Most of the daughter species resulting from the Camptostoma split are among the most encountered (or at least often-heard) tyrannulets in their range. There are many dozens (if not hundreds) of published field guides and identification resources that use the long-standing name “Southern Beardless-Tyrannulet”. There are likely even more academic publications that use both that name and the scientific name, but don’t refer to what would be meant by that combination now.

This is greatly exacerbated by how birding works in the current age. If we retain the name Southern Beardless-Tyrannulet, a birder visiting Ecuador, or Peru, or Colombia, etc., will almost certainly be using a field guide that uses that same scientific AND English name. Most birders aren’t nearly as educated about recent taxonomic updates as we all are, and when they go to eBird to log their sightings, or Merlin (or the Macaulay Library, or xeno-canto) to listen to a sound of the species, they will be directed to the wrong taxon for where they are. Local guides using English names may not be up to date on changes and thus may tell their clients the wrong species. And anyone referring to any mention of “Southern Beardless-Tyrannulet” will need to figure out if that mention is of the pre-split or post-split species.

To give an example of the staying power of this type of issue, eBird recently had to change over 1000 records of “Winter Wren” from the Himalayas, due to the retention of Winter Wren as a common name. Keep in mind that this change was from before eBird was even available in that part of the world, and from a part of the world where that name wasn’t as universally used as Southern Beardless-Tyrannulet was before that species was split.

Aligning with SACC is very high among the priorities of the AviList ENC, and they have indicated that they will very likely go along with a better suggestion than “Southern” for this taxon. The name “Subtropical” was suggested by Josh Beck, and the non-Andean portion of the range of Subtropical Doradito mirrors that of this tyrannulet (but not that of the Subtropical Pygmy-Owl). The definition of “subtropical” given by Google AI is: “geographic and climate zones immediately north and south of the Earth's tropics, typically located between 23.5° and 35° to 40° latitude”, so it is reasonably descriptive of this species’ range.

We are under a bit of a time crunch here, as the AviList ENC needs to finalize names by July 15^th. To keep things simple, this proposal offers two options: voting NO indicates that you are voting to retain Southern Beardless-Tyrannulet for Camptostoma obsoletum. YES is a vote for Subtropical Beardless-Tyrannulet.

Andrew Spencer and Pam Rasmussen, June 2026

Vote tracking chart:

https://www.museum.lsu.edu/~Remsen/SACCPropChart1044+.htm

Comments from Donsker (voting for Bonaccorso): “I completely buy the argument presented by Andrew and Pam in SACC proposal 1078 that it would be wise to reconsider the English name of Camptostoma obsoletum (sensu stritco). I vote YES for their suggested English name Subtropical Beardless-Tyrannulet.”

Comments from Zimmer: “I vote YES to change the English name of Camptostoma obsoletum (sense stricto) to Subtropical Beardless-Tyrannulet, for the reasons stated in Proposal 1078. I don’t remember that name suggestion coming up during our previous considerations, but I like it, and it seems entirely appropriate and not too unwieldy.”

Comments from Rasmussen: “I vote YES for Subtropical, which for the reasons in the proposal seems a far better name than any of the others that have been considered. The main downside that I can see is the number of syllables (10), but likely when birding I'd think people will usually just say ‘Subtropical’ or ‘Beardless’ anyway.”

Comments from Josh Beck (guest voter): “Just to give credit correctly, Subtropical wasn’t my idea; it came from friends in Argentina and Uruguay who were really happy to have been consulted. I merely passed it along! So, I’m personally very happy that a name that came from birders / ornithologists in C. obsoletum’s range is presented as an option. 

“In any case I like Subtropical essentially as well or better than any of the other options and am happy with it as the least problematic of all options suggested so far, so I vote YES to use Subtropical instead of Southern.”

Comments from Remsen: “YES in the spirit of compromise. Given that the policy that in parent-daughter splits, a daughter should not retain the parental name, I’m normally strongly in favor of that, i.e., the ‘one taxon, one name’ principle, but it’s a guideline, not a rule, and in this case “Southern” was a good name in my opinion not only because it was accurate but also because it was a nice foil to ‘Northern Beardless-Tyrannulet’.

“As with the majority of English names, it’s easy to find fault but usually difficult to find something better. In this case, ‘Subtropical’ could apply just as well to some other Camptostoma, including Northern, but so be it.”

Comments from Rosenberg: “I vote YES for Subtropical. I agree with Van that Southern still seems like a more accurate name - but I also understand the issue of confusion with older field guides - although that is an issue with many newly named species (at least in terms of not having the accurate name - but perhaps not in actually representing the WRONG species). So as a compromise, I am fine with using Subtropical (although the word Subtropical is often used to delineate an elevation difference from the “Tropical” zone - as in Subtropical Pygmy-Owl).”

Comments from Areta: “I am not sure of why this has become a Subtropical yes/no proposal. There are only 2 other "Subtropical" birds, both of which have distributions largely encompassing the Andes, in the "Subtropical zone": Glaucidium parkeri and Pseudocolopteryx acutipennis (the latter having apparently recently expanded south and east to colonize the lowlands of Argentina, as we discussed here). So, if Subtropical is to mean anything more or less precise, the third "Subtropical Beardless-Tyrannulet" would be complete mismatch to what the other names were referring to. I vote NO to Subtropical and vote in favour of Meridional Beardless-Tyrannulet. one of the names that was an option in previous proposals. Incidentally, I am perfectly fine with nominate obsoletum retaining Southern (as current SACC treatment), and I am also perfectly well with obsoletum being called Austral (as in AviList votes). So, I think that the current proposal is a step backwards in the naming of this cute little bird that is close to my heart.”

Comments from Spencer: “I obviously vote YES for Subtropical. While it, like anything else we've come up with, has some issues, I think it is the best option voiced so far. Thank you to Josh for reaching out to so many birders in Argentina, Brazil, and Uruguay, and coming back with that option! To be fair, I was also, in the end, ok with Austral (but didn't like it). In response to Nacho on Meridional, I think that word is just too obscure to be a name I'm happy voting for. If the species was some obscure tapaculo or tyrannulet on an isolated mountain range somewhere, I might be more willing to choose an essentially unknown word as the name. But for such a common species I'd rather avoid it.”

Additional comments from Remsen: “Because ‘Austral’ has emerged again, I again provide the graphics that show why ‘Austal’ is not just bad but ‘wrong’, and it would corrupt the tight connotation it has with the 7 SACC species already called ‘Austral Something’.”

Additional comments from Areta: “I have here added the missing Tropic of Capricorn to Van´s map. As can be seen, the species could have been more aptly called Tropical, if one follows the arguments against Austral (which in my mind just equates to Southern). The range of C. obsoletum in the "subtropics" is even smaller than shown, as it does not occur in the huge Puna Plateau area included in the sketch (I know it is just a fast sketch). I also don´t think that the traveler birder argument should be the main concern here: we should focus on a much broader audience of users of these names. Given the broad geographic range of obsoletum, it makes perfect sense to retain Southern for the nominate, widespread species. As such, the pretended accuracy of Subtropical vanishes and it does not match what other concepts of Subtropical have been applied to South American birds.”

Additional comments from Donsker: ““Nacho’s map helps. Perhaps we’re overlooking an obvious (albeit unlovely) name ‘Southeastern Beardless-Tyrannulet’.”

Additional comments from Rasmussen: “I still think that Subtropical is the best name we have for Camptostoma obsoletum. It gets the idea across that the distribution of this species is somewhat removed from the equator, and to me is at least as, if not more, helpful than Pacific, for example, for something that occurs along a small portion of one side of the Pacific Ocean (but I definitely am not suggesting we revisit that one!). I checked iNaturalist for usages of Subtropical in the names of other organisms, and there are several, but none have very similar distributions to C. obsoletum. If we choose to use the dictionary definition of Subtropical, then this bird gets rather too far into the tropics for it to be a perfect name, but as we all know perfect names for drab creatures are hard to come by. In thinking of other usages of Pacific for bird names, and then comparing it with how radically different those usages are to this proposed usage of Subtropical I think its usage is completely defensible. Southeastern would be serviceable, and Argentine would be fine too, but I continue to vote for Subtropical."