Proposal (389) to South American Classification Committee

 

Treat Scytalopus fuscicauda as conspecific with S. meridanus

Effect of Proposal: A Yes vote on this proposal would result in Scytalopus fuscicauda being removed from the SACC checklist, following Donegan & Avenda–o-C. (2008)

 

Discussion:

As summarised in Donegan & Avenda–o-C. (2008): Many recent authors recognise two light-plumaged Scytalopus in the Venezuelan Andes: Merida Tapaculo S. meridanus Hellmayr, 1922 is found across much of the range; and Lara Tapaculo S. (griseicollis) fuscicauda Hellmayr, 1922 is considered to be present in Lara state and on the Trujillo state border (e.g. Krabbe & Schulenberg 1997, 2003; Hilty 2003). Scytalopus fuscicauda is generally described as a high elevation bird with at most only traces of barring on its lower underparts (Hellmayr 1922, Zimmer 1939, Krabbe & Schulenberg 2003, Hilty 2003). S. meridanus has been considered a species with more strongly barred lower underparts, with higher elevation records having been doubted and some texts illustrating a rather dark-plumaged bird (FjeldsŚ & Krabbe 1990, Krabbe & Schulenberg 2003, Hilty 2003). Krabbe & Schulenberg (2003) ranked fuscicauda as a species, concluding that it was unlikely to be related to S. griseicollis. However, they noted that S. fuscicauda might be synonymous with S. meridanus and recommended further studies.

 

Donegan & Avenda–o (2008) studied plumage, biometrics and voice of northern Andean Scytalopus in connection with the description of various undescribed taxa and the naming of one of them.  Species limits were also considered.  The methods and species limit models used were similar to those applied by Isler et al. to assess antbird species limits.  The authors inspected photographs of the type specimens and analysed series of specimens and sound recordings taken from the region of the "meridanus" and "fuscicauda" type localities.  As with "infasciatus/griseicollis", considerable individual variation in the strength of vent barring was noted in MŽrida Andes populations.  No character that might define "fuscicauda", except, possibly variations in the introductory notes to songs, was noted, based on recordings by Boesman (2003) and others.  In light of the variation in introductory notes to songs within S. griseicollis and S. spillmanni this difference would not seem sufficient to recognise a species, even if borne out by further study - given that the main song phrase is otherwise indistinguishable.  A discussion for the rationale for not recognising S. fuscicauda as a species is set out on pages 40-42 of the relevant paper.

 

We concluded: "no morphometric, biogeographic, plumage, or vocal data support the treatment of S. fuscicauda as a species. Further, such a treatment should not be regarded as a "status quo" (contra e.g. Remsen et al. 2008) given that S. fuscicauda was lumped with either S. magellanicus or S. griseicollis until 2003, including by Hilty (2003) in the leading field guide for the region. Whilst we agree with Krabbe & Schulenberg (2003) that S. fuscicauda is not conspecific with S. griseicollis, the most conservative approach at present would be to treat it as a subspecies of S. meridanus. We suspect that the two taxa are synonyms but we decline to go so far, pending analysis of a greater sample of vocalizations from Lara state and other regions."

 

The names "meridanus" and "fuscicauda" were originally published in the same paper by Hellmayr (1922).  The name "meridanus" has priority as a result of Donegan & Avenda–o-C. (2008) choosing it as "first reviewers".  The concept of "page priority" (which would point to fuscicauda having priority) does not apply as a general rule to contemporaneously described species names.

 

I recommend a "Yes" vote.

 

Reference:

Donegan, T.M. & Avenda–o-C., J.E. 2008. Notes on Tapaculos (Passeriformes: Rhinocryptidae) of the Eastern Andes of Colombia and Venezuelan Andes, with a new subspecies of Scytalopus griseicollis from Colombia.  Ornitolog’a Colombiana 6: 24-65. http://www.ornitologiacolombiana.org/oc6/doneganyavendano.pdf

 

Jorge Enrique Avenda–o C., February 2009

 

Comments from Stiles: ŇYES to considering S. fuscicauda as a subspecies (at least, for the time being) of S. meridanus.  I also agree with their decision to choose meridanus as the most appropriate name for the species

 

Comments solicited from Niels Krabbe: ŇI would vote yes for treating fuscicauda as conspecific with meridanus on the grounds that their songs are similar, rendering it likely that they would interbreed if in contact.Ó

 

Comments from Nores: ŇYES, aunque no muy convencido. Los autores son muy enf‡ticos al se–alar Ňno morphometric, biogeographic, plumage, or vocal data support the treatment of S. fuscicauda as a speciesÓ, siendo que salvo el canto, ninguna de esas variables tienen mayormente importancia en separar especies. Dos especies diferentes pueden tener exactas medidas, color similar (en este caso S. meridanus en m‡s oscuro que fuscicauda, o sea que hay alguna diferencia) y distinto canto, por ejemplo. Lo de diferencias biogeogr‡ficas es tambiŽn muy relativo. Yo creo que en este caso se trata de subespecies porque tienen el canto similar y algunas diferencias en plumaje

 

Comments from Zimmer: ŇYES.  Given that the only vocal difference is in the introductory notes of the songs.  I think you really have to be careful with how you treat differences in the introductory notes of these tapaculos.  From my own experience, there is a lot of variation in the introductory notes from one song to the next within the same individual of many species.  One song will start with one or more highly differentiated notes, and the next wonŐt have any differentiated notes at all.  Also, I find that when recording spontaneous songs of Scytalopus, I often miss the first few notes and end up recording a long song without the intro.  Then, the bird shuts up, and when it eventually responds to playback, it often leaves out the intro notes.  The end result is that a lot of audio archives may be undersampling the intro notes of tapaculo songs, which can make analysis even more treacherous.Ó

 

Comments from Jaramillo: ŇYES Đ Vocal differences, which are important in this group are weak.Ó

 

Comments from Pacheco: ŇYES.  A partir das informaŤ›es aqui expostas eu aceito a subordinaŤ‹o de fuscicauda com meridanus. Concordo com Kevin que aludidas diferenŤas nas notas introdut—rias podem ser Đ esperadamente Đ meros artefatos de amostragem nesse grupo.Ó