Proposal (555) to South American Classification Committee
Reclassification of the Scolopacidae
Effect on SACC: This proposal would divide our current family Scolopacidae
into 5 subfamilies and change the sequence of genera within the family.
Background: Our current classification does not include subfamily
structure and follows a traditional sequence of genera. The reason for the lack of subfamily
structure was our wise assessment of the lack of concordance among other
classifications and the absence of a solid DNA-based phylogeny. Our footnote is as follows:
1. <note on genera, linear sequence> Jehl
(1968b). The family Scolopacidae is traditionally split into five or more subfamilies
and additional tribes (e.g., AOU 1998).
Livezey
(2010) recognized four subfamilies (Arenariinae, Calidrinae, Tringinae,
Scolopacinae) and maintained the phalaropes as a separate family. Genetic data (e.g. Gibson & Baker 2012), however,
provide very weak or no support for the monophyly of these groups, and although
the phalaropes are monophyletic, they are deeply embedded in the Scolopacidae
and sister to the tringines.
Gibson & Baker (2012) identified five major lineages in the
family. SACC proposal needed to recognize five subfamilies.
New information: Gibson & Baker (2012)
produced a phylogenetic hypothesis based on strong taxon-sampling (84 species)
and good gene-sampling (6300+ bps; 1 nuclear + 4 mitochondrial genes). Branching patterns in general were
well-resolved (except for problems within the explosive calidridine
radiation). Here is their tree
– sorry about the poor resolution – if anyone needs a pdf, just let
me know:
I suggest that the best interpretation of the tree is to
recognize 5 major lineages and to give each one subfamily rank. Note that Gibson & Baker name 8
groups, not 5, which would be an alternative treatment, i.e. 8 subfamilies. I suggest condensation to five for the
following reasons.
(1) The Snipe-Dowitcher-Woodcock group is probably best
treated as a single group because the branch lengths connecting them are very
short, inclusion of Limnodromus
semipalmatus in the Dowitchers has weak support, and taxon-sampling within
the Woodcock and Snipe groups is weak (including absence of Limnocryptes).
(2) The Phalaropes if treated as a subfamily would
technically also have to include Xenus
(Terek Sandpiper), which groups with them albeit with substandard support. That result is best treated as
anomalous, in my opinion, until corroborated by additional data (parallel to
the initial anomalous results for Pluvialis;
see Baker et al. 2012). An
alternative approach would be to recognize the Phalaropes as a subfamily and to
retain Xenus in its traditional spot
in the Tringinae or place it as Incertae Sedis. Although not giving the phalaropes subfamily rank might seem
extreme, keep in mind that Phalaropus
tricolor (which really deserves to have its monotypic genus status
reinstated: Steganopus) strikes many
field people as having some tringine-like behaviors.
Tangentially, I take the opportunity to point out that
Livezey (2010) placed the phalaropes in their own family, as they were for most
of their history due to their unusual morphology. Assuming that the gene-based phylogeny reflects historical
relationships, this is yet another warning for use of morphological data to
infer phylogeny. Livezey’s careful
and quantitative analysis of hundreds of phenotypic characters was unable to
distinguish highly derived morphological change from lineage history, just as
it was unable to identify strongly convergent morphology (e.g., Livezey’s
sister relationship between Podicipedidae and Gaviidae).
Another point worth considering is giving subfamily rank to
the Turnstones. Although not
labeled as a group by Gibson & Baker, just looking at relative divergence,
they deserve naming if Woodcocks, Snipes, and Dowitchers do, and their
distinctive morphology has led to their classification as a separate family or
subfamily in the past. But looking
at branch lengths and node depths in the tree, if turnstones are treated as a
subfamily, then snipes, woodcocks, and dowitchers also should be. As predicted from any categorical
scheme inflicted on a continuum of differentiation, borderline situations are
inevitable. I suggest that that if
we decide to include the Tribe level in our classification, then turnstones
would be a prime candidate for recognition at that level.
Taking the Gibson-Baker tree and transforming it to a
classification for species in the SACC area, including changes in species
sequence to match the tree, would look like this:
SCOLOPACIDAE
(SANDPIPERS)
Numeniinae
Bartramia longicauda Upland
Sandpiper
Numenius borealis Eskimo Curlew
Numenius phaeopus Whimbrel
Numenius americanus Long-billed Curlew
Limosinae
Limosa lapponica
Bar-tailed Godwit
Limosa limosa Black-tailed Godwit
Limosa haemastica Hudsonian Godwit
Limosa fedoa Marbled Godwit
Arenariinae
Arenaria interpres
Ruddy Turnstone
Arenaria melanocephala Black Turnstone
Aphriza virgata Surfbird
Calidris canutus Red Knot
Calidris alba Sanderling
Calidris pusilla Semipalmated Sandpiper
Calidris mauri Western Sandpiper
Calidris minutilla Least Sandpiper
Calidris fuscicollis White-rumped Sandpiper
Calidris bairdii Baird's Sandpiper
Calidris melanotos Pectoral Sandpiper
Calidris alpina Dunlin
Calidris ferruginea Curlew Sandpiper
Calidris himantopus Stilt Sandpiper
Tryngites subruficollis Buff-breasted
Sandpiper
Philomachus pugnax Ruff
Scolopacinae
Limnodromus griseus
Short-billed Dowitcher
Limnodromus scolopaceus Long-billed
Dowitcher
Gallinago imperialis Imperial Snipe
Gallinago jamesoni Andean Snipe
Gallinago stricklandii Fuegian Snipe
Gallinago nobilis Noble Snipe
Gallinago undulata Giant Snipe
Gallinago delicata Wilson's Snipe
Gallinago paraguaiae South American Snipe
Gallinago andina Puna Snipe
Tringinae
Phalaropus tricolor
Wilson's Phalarope
Phalaropus lobatus Red-necked Phalarope
Phalaropus fulicarius Red Phalarope
Xenus cinereus Terek Sandpiper
Actitis macularius Spotted Sandpiper
Tringa solitaria Solitary Sandpiper
Tringa incana Wandering Tattler
Tringa melanoleuca Greater Yellowlegs
Tringa semipalmata Willet
Tringa flavipes Lesser Yellowlegs
Tringa glareola Wood Sandpiper
Additional points:
1. The above does not deal with the problems of generic
limits in the Calidrinae, e.g., sister relationship of Aphriza to C. canutus;
see Banks (2012). Dick Banks is
submitting a proposal to NACC on this, and I suggest we do not meddle until
dust settled.
2. The sequence from Xenus
through T. glareola now conforms to
current NACC sequence.
3. SACC proposal 548 would
split Chubbia from Gallinago, but that would not change the
linear sequence of species.
4. Banks (2012) used Arenariinae Stejneger,
1885, as the subfamily name, even though Calidrinae Reichenbach, 1849, is older
name: “The family-group name for the turnstones was
originally based on the generic name Strepsilas Illiger, 1811 by Gray
(1840), as Strepsilinae (fide Bock 1994:138). Stejneger (1885:95) introduced
the name Arenariinae, based on Arenarius Brisson, 1760, a name with many
years priority over Strepsilas, and it thus became the proper name for
the subfamily (see Ridgway 1919:42). For purposes of priority, Arenariinae
dates from 1840 (ICZN 1999, Art. 40.2). The name Calidridinae was not
established until l849 (fide Bock 1994:138) and thus is a junior synonym of
Arenariinae.”
Discussion & Recommendation: See proposal 552 for my views on the value of using additional ranks,
in this case subfamily, in our classification. I am open to alternative classifications, but barring viable
alternatives, I recommend a YES on this as improving the information content of
our classification.
Literature:
BANKS,
R. C. 2012. Classification and
nomenclature of the sandpipers (Aves: Arenariinae). Zootaxa 3513: 86-88.
GIBSON,
R., AND A. BAKER. 2012. Multiple gene sequences resolve phylogenetic
relationships in the shorebird suborder
Scolopaci (Aves: Charadriiformes). Molecular Phylogenetics and
Evolution 64: 66–72.
LIVEZEY,
B. C. 2010. Phylogenetics of modern
shorebirds (Charadriiformes) based on phenotypic evidence: analysis and
discussion. Zoological Journal of the
Linnean Society 160: 567-618.
Van Remsen,
October 2012
Comments from Stiles:
“A very qualified YES (but note that Chubbia is not reinstated here but will
be if 546 passes. Also see the extensive Raty commentaries on the Scolopacidae
in the “TiF Classification” (whatever this is). Note that here Calidris is restricted to canutus and a couple of OW species, and
includes Aphriza; all the smaller Calidris are treated in Ereunetes. Also, Limicoli is considered to have priority over Scolopaci
(or -inae, for subfamilies). These
points seem worth considering.”
Comments from Pacheco: “YES. Considerando todos os pontos, incluindo os adicionais.”
Comments
from Cadena:
“YES (see
comments under proposal 552).”
Comments
from Pérez-Emán: “NO. I like this proposal better than previous ones
on the same topic (552 and 553) because it incorporates some behavioral and
morphological issues into the discussion (in the case of Phalaropes and
Turnstones). However, integrating such information provides an interesting
example about how different interpretations of the same data might result in a
different subfamily classification (discussions in Gibson & Baker (2012)
and in this proposal). Moreover, as pointed out by Remsen, depending on the
importance or interpretation given to branch lengths or node depths in the
tree, one can come out with different subfamily arrangements. Thus, such
borderline situations discussed by Remsen could be more the rule than the
exception and might result in non-meaningful classifications at the subfamily
level.”
Comments from Nores: “YES. This seems like the best way to go given available evidence.”