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.”