Proposal (546) to South American Classification Committee

Resurrect Chubbia

Effect on South American CL: This proposal would resurrect a genus for three Andean species currently placed in Gallinago (imperialis, jamesoni, stricklandii).

Background: Three species of Andean snipe were traditionally (e.g., Peters 1934, Hellmayr & Conover 1948) placed in a separate genus, Chubbia, from Gallinago. In fact, Hellmayr’s and Conover’s footnote compared Chubbia to the woodcock genus Scolopax, not Gallinago, even though he used the English name “Snipe” for the three species (imperialis, jamesoni, stricklandii):

“Genus Chubbia Mathews: Like Scolopax in having the tarsus posteriorly covered with small hexagonal scales, but bill longer, tarsus much stouter, and tail composed of fourteen feathers.”

Chubbia was first merged, as far as I can tell, into Gallinago by Meyer de Schauensee (1966), and that’s the way it has been ever since.

New information: Using DNA sequence data from nuclear (RAG1) and mitochondrial (cyt b, ND2, COI) DNA, Gibson & Baker (2012) sampled 7 species of Gallinago, 2 Coenocorypha (tiny woodcock-like snipe from islands near New Zealand), and 2 Scolopax, and found that “G.” imperialis was the sister to the 2 Coenocorypha with strong support. (Gibson & Baker evidently did not comment on this rather remarkable finding in terms of biogeography.) Thus, Gallinago as currently defined is paraphyletic. One solution would be to expand Gallinago to include Coenocorypha, as well as unsampled Limnocryptes, but this is beyond the aegis of SACC. A simpler and more sensible solution would be to resurrect Chubbia. In fact, one could make a case for this solely on the absence of any published rationale for its merger into Gallinago.

Discussion: I am not familiar with the three species that comprised Chubbia, but evidently, few people are. Frankly, I did not realize how woodcock-like these three species are in terms of morphology, habitat preferences, and nocturnal behavior before investigating the demise of Chubbia. As far as I can tell, all three are rare, nocturnal species of the high Andes or austral lowlands that apparently roost in wooded areas and then feed and display in bogs or grassy areas …. i.e. somewhat more woodcock-like in being tied to wooded areas more than are most snipe. Their bills are also more woodcock-like in being slightly down-turned.

Fjeldså & Krabbe (1990) noted:

“These two forms [stricklandii and jamesoni] and the Banded [Imperial] Snipe are intermediate between the smaller snipes and the stocky woodcocks (Scolopax) of other continents; stricklandii being most snipe-like, the Banded Snipe very similar to the Dusky Woodcock (S. saturata) of Java and New Guinea. The ‘woodcock-snipes’ are sometimes placed in a separate genus Chubbia.”

Here is a link, courtesy Alvaro, to a video of stricklandii:

http://www.youtube.com/watch?v=I8HyKtHoAnY&feature=player_detailpage

All of this is qualitative, superficial, and potentially irrelevant – there is no reason why some snipe would not converge on “woodcockness”, and in fact there may be a continuum between the two groups in ecology and morphology. My only point, a weak one, is that these three species may not be typical Gallinago snipe.

Recommendation: Reasons for rejecting this proposal would be that only 1 of the 3 Chubbia were sampled by Baker, and that a safer solution would be to retain them in Gallinago pending further sampling, including more Gallinago species and also Limnocryptes. I favor resurrecting Chubbia because I think that the limited data so far puts the burden-of-proof on the position that merges it into Chubbia, especially because no explicit rationale was published for its merger into Gallinago. Further, to maintain broad Gallinago endorses a genus that is paraphyletic with respect to extralimital Coenocorypha.

References:

GIBSON, R., AND A. J. BAKER. 2012. Multiple gene sequences resolve phylogenetic relationships in the shorebird suborder Scolopaci (Aves: Charadriiformes). Molecular Phylogenetics and Evolution 64: 66–72.

Van Remsen, September 2012

Additional message from Thomas Donegan: “Van, not sure if you have seen this very interesting discussion / critique of the recent molecular paper from Laurent Raty? It seems relevant to your recent proposal, though imperialis still comes out closer to the Australasian species in his revised tree.

http://www.birdforum.net/showthread.php?t=171100

Comments from Zimmer: “NO. I’m conflicted on this one. Given that only 1 of the 3 Chubbia were sampled, and given that G. undulata (morphologically more woodcock-like, and decidedly crepuscular, although found in open marshes, not wooded areas) is not treated as part of Chubbia, I’m thinking that it may be safer to leave everything in Gallinago until more taxa have been sampled. If we make the move now, we may subsequently find that Chubbia is not monophyletic, and neither is Gallinago (depending on where undulata falls out). So, a rather weak ‘NO’ vote from me.”

Comments from Stiles: “YES.  The morphological similarities between jamesoni, stricklandii, and imperialis have long been recognized, and the clear genetic differences between the latter and the Gallinago snipes makes it at least more likely that the former two will fall with imperialis. Given that the original lumping of Chubbia into Gallinago was apparently not supported by any real data, and that including imperialis would render Gallinago polyphyletic, the weight of evidence now supports recognition of Chubbia.”

Comments from Pacheco: “NO. Aguardando uma análise com cobertura melhor de táxons.”

Comments from Jaramillo: “YES – having looked at a lot of snipe skins over time, I always wondered why Chubbia was dropped. It looked like a fine subset in the woodcock-snipe clade. I think that some shifting may occur as we find out more, but including Chubbia improves the taxonomy of this group.”

Comments from Nores: “NO. Although Van’s proposal seems a simpler and more sensible solution for stricklandii, only 1 of the 3 “Chubbia” was sampled by Gipson and Baker. For this reason, I prefer to retain them in Gallinago pending further sampling.”

Comments from Robbins: “NO, given the incomplete sampling coupled with what I consider to be very surprising results (imperialis sister to Coenocorypha). Thanks to Thomas Donegan, I looked at Laurent Raty’s critique and reanalysis of the data set. Raty discovered misidentified taxa (e.g., a purported Gallinago apparently is a Limnodromus; sample EF373132) and issues with some of the sequences; this, coupled with the missing taxa makes me uneasy about making a change now. I believe Van’s cautionary statement in proposal 549, “…is an excellent example of why odd findings should require corroboration with additional data”, seems germane here as well.”