Recognize newly described Synallaxis beverlyae Hilty and Ascanio, 2009
Background: Hilty and Ascanio (2009) discovered and described a new species of Synallaxis, S. beverlyae, from river islands in the Orinoco based on 9 specimens deposited in the Phelps Collection. As far as is known, it is narrowly restricted to early successional vegetation on the upper Orinoco.
In plumage and morphology, the species is most similar to but diagnosably different from S. albescens and S. spixi. On plumage and morphology alone, it seems unquestionably a new taxon. See the original paper for details.
Based on voice, the authors assign species rank to the new taxon. It falls within the group of Synallaxis that have a series of 4 or more notes in their primary vocalizations with an emphasized introductory note, i.e., S. albigularis, S. hypospodia, and S. spixi, and not the group that contains S. albescens. Hilty and Ascanio analyzed recordings from two localities and compared them to a good sample of recordings of other species, including those most similar in plumage and voice, and beverlyae differs from any similar-sounding species in length, pitch, or number of notes. Therefore, the authors reason that it should be ranked as a species. It is syntopic with S. albescens (which may account for the plumage similarities).
Analysis/Recommendation: Based on voice and habitat preference, I suspect that the new taxon is most closely related to S. albigularis, which is absent from the Orinoco. They differ in voice in that beverlyae has a higher-pitched, less nasal primary vocalization. I agree whole-heartedly with the authors’ statement “… the suite of differences in habitat, voice, and plumage among S. beverlyae and other species in the genus suggest that it has diverged to the level associated with species-level differences in this genus. The differences between it and its presumed closest allies are as great or greater than those among many currently recognized species in the genus.” I see no reason not to vote YES on this one.
HILTY, S. L., AND D. ASCANIO. 2009. A new species of spinetail (Furnariidae: Synallaxis) from the Río Orinoco of Venezuela. Auk 126: 485_492.
Note: The authors suggested “Rio Orinoco Spinetail” as the English name, and I see no reason not to start with that. I’m not sure why it couldn’t be just “Orinoco Spinetail” except that it emphasizes that the bird is really only on the Orinoco itself rather than the region.
Van Remsen, August 2009
Comments from Stiles: “YES, this seems to be a well-argued case for species recognition. Might it occur in Colombia??”
Comments from Nores: “YES. Los fundamentos dados en la propuesta y en el paper resultan bastante convincentes. La única cosa que me llama la atención es que se menciona en la diagnosis que la nueva especie es parecida a Synallaxis albescens y a Synallaxis spixi, siendo que S. albescens y S. spixi son marcadamente diferentes entre si. S. albescens es casi blanco de abajo, pardo de arriba y tiene la frente parda, mientras que S. spixi es muy oscuro, plomizo, tanto de arriba como de abajo y tiene la frente rufa como el resto de la corona.”
Comments from Zimmer: “YES. Hilty and Ascanio have clearly demonstrated the distinctiveness of this species, which, in plumage characters is closest to S. albescens (The two species are widely syntopic with no evidence of interbreeding; all observed pairs in areas of overlap assortatively mated.), but in vocal characters is closer to S. albigularis, which is not present in the Orinoco region. Having seen and tape-recorded multiple individuals of S. beverlyae myself, I have no doubts as to its validity as a good biological species.”
Comments from Pacheco: “YES. O táxon recém-descrito é plenamente diagnosticável.”
Comments from Jaramillo: “YES. This is a well-argued paper that confirms that this is a new Synallaxis, based on voice, habitat, morphology etc. I see no red flags that suggest waiting for further information; it seems a clear-cut new species.”