Proposal (513) to South American Classification Committee

 

Change English name of Scytalopus panamensis to "Tacarcuna Tapaculo"

Background:   Wetmore (1972) suggested the split of Scytalopus vicinior from Scytalopus panamensis.  This split has been followed generally since then.  At that time, Wetmore maintained the English name Pale-throated Tapaculo for S. panamensis.  Pale-throated Tapaculo was used exclusively as far as I can tell until Ridgely and Gwynn (1989) used the English name Tacarcuna Tapaculo for S. panamensis.  This new name has been adopted by many references since that time including the 7^th edition of the AOU checklist (1998), Sibley and Monroe (1990), and the IOC.  SACC based on Dickinson (2003) continued to use Pale-throated, as did Clements, 6^th edition (2007).

 

Commentary:   There are two reasonable English names for this species.  Other than listings of species, there is actually almost no literature that uses the English name for Scytalopus panamensis as currently constituted.  For example, Krabbe and Schulenberg (1997) mentioned S. panamensis, but did not provide an English name for it.  Pale-throated is not very descriptive and doesn’t mention the one plumage character that sets this species apart, a long, pale superciliary.  But it is the name with a history.  I haven’t confirmed this, but think that the name was invented by Eisenmann in 1955.  Unfortunately most of that history occurred while it was used for a different species concept of Scytalopus panamensis, one that included Scytalopus vicinior (Nariño Tapaculo) within it.  Ordinarily (but not always) when the taxonomy of a species is changed, the English name is changed to reflect the fact that the new species consists of a different set of taxa, even though the scientific name remains unchanged.  This general guideline is most often not maintained for species that are widespread, from which species with much smaller ranges are removed (e.g. Herring Gull with the removal of Thayer’s Gull and various yellow-legged forms included or not).  

         In this case, the remnant Scytalopus panamensis has a tiny range restricted to the Tacarcuna range right on the border between Colombia and Panama, whereas S. vicinior ranges from eastern Panama to northwestern Ecuador.  The name Tacarcuna Tapaculo describes well the range of panamensis, and this is the only species of tapaculo in the range.  Scytalopus vicinior seems to have always been known as Nariño Tapaculo since its split.  I suspect that because of its more extensive range and the greater accuracy of the name that the name Pale-throated Tapaculo was applied to the species S. panamensis really as a descriptor of vicinior, not the nominate form.

Recommendation:

         Although I am generally hesitant to change English names, I think adopting the name Tacarcuna Tapaculo for Scytalopus panamensis makes sense.  It is in general use because it is used in the Panama field guide and has been adopted by the AOU North American Committee.  It is a “better” name than Pale-throated, and accurately describes the range of a very narrowly distributed species.  The name Pale-throated does not describe a field mark for this species.  Range and voice would be the characters used to identify this species in the field.  I recommend a Yes vote on this proposal.

 

Doug Stotz, January 2012

 

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Comments from Jaramillo: “YES – This seems reasonable, and it is distinctive.”

 

Comments from Stiles: “YES.  In general, I favor toponyms for species with very narrowly restricted ranges, especially when the previous name is non-distinctive (and especially in groups with many similar species, like tapaculos, Myioborus, etc.).”

 

Comments from Zimmer: “YES for reasons nicely summarized by Doug.  I echo Gary’s appreciation for toponyms for species with tiny geographic ranges.  So-called “descriptive names” in groups like Scytalopus are usually anything but, and only add to confusion by suggesting that a species is more different morphologically than it actually is.”