Proposal (765) to South American Classification Committee

Recognize Anthus peruvianus as a separate species from Anthus lutescens

Effect on SACC: This would split Anthus peruvianus from A. lutescens.

Background & New information: The current classification considers the taxon peruvianus to be a subspecies of A. lutescens, following most recent classifications.

Analysis 

According to new multilocus (ND2, ACOI9, MB, FGB5) genetic data (Van Els & Norambuena 2017), the taxon peruvianus is not part of A. lutescens. Its exact placement is uncertain given rather low support values (despite full sequence sampling for the taxon), but a Shimodaira-Hasegawa test indicated that it is most likely sister to a group including A. lutescens, A. furcatus, and A. spragueii, rather than to a group including A. chacoensis, A. nattereri, A. correndera, A. antarcticus, and A. hellmayri. It is therefore best placed before A. lutescens in the linear sequence of Motacillidae, pending further evidence.

To back up genetic data, songs of peruvianus differ consistently from those of A. lutescens (incl. subsp. lutescens, and individuals from northern South America, referred to in the article as subsp. ‘abariensis’, vocal data of subsp. parvus from Panama was unavailable), within a vocal dendrogram of all Neotropical pipits, they do not cluster with A. lutescens, but are rather at the base of all individuals that have a buzz in their song.

Finally, peruvianus is geographically isolated from A. lutescens by the Andes, and it lives in a rather different environment than that species. Where A. lutescens utilizes all sorts of grassy and agricultural, open habitats in (mainly) the tropical lowlands east of the Andes, peruvianus is restricted to a fairly narrow coastal strip of fog-induced desert vegetation in Peru and extreme northern Chile.

As a side-note, del Hoyo and Collar (2017) already recognize A. peruvianus, based on the Tobias yardstick method and the fact that it “differs in its clearer whitish supercilium; slightly broader, more diffuse dark streaks on upper breast, without buff fringes, and extending onto flanks; stony-white vs yellowish-white underparts; longer wing but shorter tail; very different song and call.”

Conclusion

We recommend splitting peruvianus from A. lutescens, and using the English name Peruvian Pipit (the species’ range is almost entirely within Peru, and a comprehensive biogeographical name for the entire coastal arid strip from northern Peru to the Peruvian-Chilean border would have been more appropriate but is apparently not available). Given the facts stated above, A. peruvianus should precede A. lutescens in the linear sequence of Motacillidae.

References

del Hoyo, J. & Collar, N. (2017). Peruvian Pipit (Anthus peruvianus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/1344119 on 15 July 2017).

Van Els, P. & H.V. Norambuena. 2018. A revision of species limits in Neotropical pipits Anthus based on multilocus genetic and vocal data. Ibis 160: 158-172.

Paul van Els & Heraldo V. Norambuena, July 2017

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Comments from Stiles: "YES, again supported by multiple lines of evidence: genetic, vocal, ecological and biogeographical."

Comments from Areta: "YES. A long-known split that was awaiting for a serious job. The drastic vocal and plumage differences coupled to molecular phylogenetic data leave no doubt."

Comments from Remsen: "YES. Seldom is a decision so easy. Here is the tree from van Els and Norambuena:

"Also, on English names, this is a case in which the "new names for daughters" guideline does not apply. First, peruvianus is not a daughter species of lutescens in the taxonomic sense. It's not even in the same branch as lutescens. Further, even in the non-taxonomic sense, lutescens is such a widespread species with such a well-established English name, compared to narrowly distributed peruvianus, that I object to destabilizing the English name for the species."

Comments from Zimmer: “YES. This is about as close to a ‘slam-dunk’ in my opinion, as we can expect to find when it comes to sorting out species-limits in oscine passerines. The song of peruvianus is off-the-charts different from that of lutescens everywhere else, which, combined with the noted genetic, morphological and ecological differences, makes for an airtight case. I remember commenting on the vocal distinctiveness of peruvianus (relative to Yellowish Pipits elsewhere) to Dan Lane 15-20 years ago when he joined our group for a morning north of Lima, and expressing the opinion that there was no way that peruvianus was the same species. I’m glad to see the authors nail this one down. I agree with Van’s reasoning that this is one of those cases where we should not mess with the English name of the widespread species (in this case, lutescens), and just worry about the coining of an English name for peruvianus. “Peruvian Pipit” makes perfect sense to me.”

Comments from Jaramillo: “YES. Years ago, when I first heard and saw peruvianus, my jaw dropped. This was the “Yellowish Pipit” that I had been looking for in northern Chile? I was confused, and at first thought, well surely this cannot be the Yellowish Pipit that is found here, maybe it is something altogether different, perhaps even new. Obviously, it was a case of two entirely different creatures being lumped under one species, and I am glad that we can finally give species status to peruvianus.”

Comments from Claramunt: “YES. The evidence is overwhelming.”

Comments from Pacheco: “YES. All available evidence from multiple data corroborates this split.”

Comments from Robbins: “YES, for recognizing peruvianus as a species, based on all data sets.”